CDA Journal Volume 31, Number 5 Journal may 2003

departments 371 The Editor/Saboteurs Within 374 Feedback/Editorial Provides Inspiration 377 Impressions/Grant Promotes Diversity of State’s Dental Workforce 446 Dr. Bob/Pitfalls of Being a Patient-Record Pack Rat features

387 Pain and Anxiety Control in -- This Is No Humbug An introduction to the issue. Tim Silegy, DDS

388 Local Anesthetics in Dentistry: Then and Now The advent of local anesthetics with the development of nerve blockade injection techniques heralded a new era of patient comfort while permitting more-extensive and invasive dental procedures. Alan W. Budenz, MS, DDS, MBA

397 -Oxygen: A New Look at a Very Old Technique With proper administration and well-maintained equipment, the nitrous oxide-oxygen technique has an extremely high success rate and a very low rate of adverse effects. Stanley F. Malamed, DDS, and Morris S. Clark, DDS

405 An Overview of Outpatient and General for Dental Care in California Principal pharmacologic interventions for the management of pain and anxiety in the apprehensive dental patient include oral se dation, intravenous sedation, and general anesthesia. Tim Silegy, DDS, and Roger S. Kingston, DDS

413 Pediatric Oral Conscious Sedation Oral conscious sedation can be a safe and cost-effective alternative to intravenous sedation and general anesthesia for children who could not otherwise be treated. Tim Silegy, DDS, and Scott Jacks, DDS

419 Current Concepts in Acute The “typical” prescription to manage moderate to severe dental pain does not necessarily reflect the current literature on oral analgesics. Mai-Phuong Huynh, DDS, and John A. Yagiela, DDS, PhD

428 Current Concepts in Chronic Pain Management Treatment planning for chronic pain may include physical, pharmacological, and behavioral aspects. Steven B. Graff-Radford, DDS

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Editor cda journal, vol 31, n 5 º

Saboteurs Within

Jack F. Conley, DDS

entistry can point to many stan- tion, the Pierre Fauchard Academy, the to separate these individuals from the dards and accomplishments, programs or projects of many other orga- profession they are demeaning by their both old and new, in which it nizations such as Su Salud and AYUDA, villainous acts. can take pride. or individual contributions that have Of what then are these saboteurs D Strong codes of ethics and supported dental care or dental research. guilty? They design and carry out entre- professional conduct are long-time stan- These achievements are regularly detailed preneurial schemes that have an objec- dards that are at the very foundation of in dental publications. They are worthy of tive of fraudulently billing the Medi-Cal the profession. They remain at the center discussion by the profession when debate system (Denti-Cal) for care not delivered, of the profession’s efforts to govern itself on dental health issues is before legisla- or for care that is not appropriate or not and develop discipline and guidelines tors. delivered by properly trained individuals. for its members. These standards have However, beyond these limited audi- who engage in these schemes contributed significantly to the image of ences, dentistry’s standards and accom- are of course the worst offenders, as they the profession. plishments tend to become invisible to violate the codes of their profession and Additionally, both individually and the public. And the public sector is where are guilty of public fraud. It is equally collectively, dentists have done much the saboteurs working within the profes- distressing that some nondentists or to advance efforts aimed at preventing sion seem to be regularly bashing the unlicensed “dentists” plan or participate dental disease. image that so many have worked so hard in these crimes that bring negative public Many dentists can take pride in their to establish and maintain. attention to the dental profession. efforts to lift the image of the profession Some of the saboteurs are licensed Within the past few months, we through endeavors to fluoridate com- dentists, some of them are dentists not noted two such reports in the public munity water supplies, contributions licensed in California, and others aren’t press. One involved a dental clinic owned to community dental health education, dentists at all but, when located, are and operated by a licensed (who participation in community dental health found practicing dentistry or managing recently had became a new member of a screenings, treatment of children in practices! component dental society) that employed underserved communities in California The relative obscurity of the activi- a nondentist who produced much of the or abroad, or direct charitable giving. A ties of these saboteurs makes it unlikely treatment that was billed to Medi-Cal. In new example of this contribution was that they become accountable to the peer eight months during 2002, investigators the recent “Give Kids a Smile” day, which review and judicial review procedures of apparently uncovered $60,000 in fraudu- brought dentists, dental students, dental organized dentistry. Yet they ultimately lent Denti-Cal billings before closing the staff, dental association staff, and many become very visible to the public. Why? office. others together in a cooperative effort They make the headlines all too regu- Less than 30 days later, another report to provide care for countless numbers of larly in newsprint or on television. Their titled, “Dental Clinics Charged With Bilk- children across the country. negative contributions to the public good ing Medi-Cal” appeared. Eight individuals, Another effort that has grown might- seem to get more attention than the most of whom the reader of this press ily in recent years is charitable giving positives that the profession contributes. report would presume were not dentists, aimed not only at providing care for those In the process, these saboteurs tear down were charged with bilking Denti-Cal out unable to afford it, but also at advancing the good image so many others continual- of $380,000 during their operation of four research efforts that will help to further ly work so hard to build, because the news clinics. control dental disease. Dentistry can be stories that describe their deeds always Too often we have been hearing of proud of its increasing contributions to include references to such familiar terms fraudulent business practices in dentistry. oral public health, whether it has been the as dentistry, dentist, and dental clinics. New or young dentists, often shouldering California Dental Association Founda- The public in many instances is unable heavy educational debt, are often targeted

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and ultimately become victims of these ing their personal identities and resisting schemes. They may become victims while the temptation to engage in suspicious engaged in a practice or even after they or risky business opportunities without have left employment in these practices. carefully evaluating them. Only under Fraudulent Denti-Cal billings are often those circumstances will we be able to made using the license and Denti-Cal pro- remove the most gullible targets of these vider numbers of former dentist employ- saboteurs at work within the dental ees. Young dental graduates must become profession. more vigilant in protecting their ID Educational efforts will not eliminate information, although in many cases it is the entire problem, but they will at least extremely difficult when they have left an help to prevent well-meaning members office to protect their personal informa- of the profession from being victimized tion from illegal use by people who have and prosecuted for crimes they did not previously gained access to it. consciously commit, a scenario that is too Due to the fact that some of the often encountered. perpetrators of this activity are either unlicensed, or are not even dentists, there is no easy solution to controlling this problem for the dental profession. While dentists are directly responsible for many of these crimes, it is not an activity that the profession has a self- governance mechanism to identify. This fraud is invisible until suspicious practice billing trends, reports from patients or former employees, or suspicions of other dentists in the community lead to audits conducted by state investigators. There are apparently about two dozen active investigations involving suspected dental Medi-Cal fraud cases currently under way in California, according to the press reports we have reviewed. Fraudulent Denti-Cal billing IS a black eye to the image of the dental profession. The dental profession does not have a good deterrent that will discourage these individuals who work quietly and invis- ibly until a billing trend is uncovered or a suspicion helps to bring them to justice. Potentially, the best deterrent may be bet- ter education of the young professional to identify and avoid this danger. New members of the profession who are heavily in debt must be counseled or mentored on the importance of protect-

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Editorial Provides Inspiration

Roseann Mulligan, DDS, MS

am hopeful that your editorial “Side Broussard’s championing of the strate- Good for a Horselaugh by Side” in the February 2003 issue of gic plan, which incorporated the ad hoc Bob Horseman’s piece in the the Journal of the California Dental diversity committee’s recommendations February 2003 issue of the Jour- Association (Page 97) will provide and adapted the leadership and members nal (“Don’t Make Me Take off My the springboard for renewed in- to the concept of inclusiveness. I await Dr. Belt,” Page 174) was pure gold! Ivolvement in organized dentistry. It was Debra Finney’s assent to the CDA presi- I am one of the 37 dentists sill alive copied and sent by the National Dental dency, which will signal another empow- who clearly recall the Doriot handpiece. Society of the Bay Area (a component ering message that CDA is changing for And my wife is one of the four living of the National Dental Association) to the better with our first woman president. registered dental assistants who re- its members. We had no expectation Your editorial has challenged me, member it. I read the article to her in that the CDA Journal would publish an inspired me, and placed an onus of its entirety. This, by the way, was one enlightened editorial that avowed our responsibility on me to assume an ac- of the few times in our marriage that history as African-American dentists tive member role. As you wrote in your I have been allowed to complete more and sincerely deplored the sordid period editorial, there were African-American than three sentences without inter- in our history when African-Americans dentists who risked great humiliation ruption. My wife loved the article, and were denied membership in the Ameri- to protest professional racial segrega- we had several good laughs together in can Dental Association. The expressions tion so that African-Americans could the process. Thank you for helping to from my colleagues emanated sensitivity, join ADA. I owe a great debt of thanks to save our fragile marriage of 51 years. courage, morality, ethics, and vision. them and to the formidable and visionary I wish Bob Horseman many more As a member of the National Dental ADA leaders who voted to ban all racially years of health and happiness. Please Association House of Delegates, I have motivated membership restrictions. keep those great articles coming. observed the shift in relationship between As a member of the National Dental ADA and NDA, moving from strictly con- Association and ADA/CDA, I can em- Gerald L. Vale, DDS, MPH, JD Poway, Calif. genial to collaborative. This improvement brace this juncture where “dentists of was initiated with the appointment of Dr. every ethnicity and background must James Bramson as the executive director stand side by side to vigilantly guard our of ADA. This collaborative relationship profession.” I must thank you for the motivated me to become a member of eloquent and passionate reminder, which organized dentistry -- ADA, CDA, and purveys the message of Dr. Edward Scott, the Alameda County Dental Society. former NDA president, “Let us focus In the relatively short time I have been on the common ground that unites us a CDA member, I have noticed that the and not on the issues that divide us.” organization is changing for the better. I joined CDA in time to witness Dr. Jack Pamela Arbuckle Alston, DDS, MPP Oakland, Calif.

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Impressions cda journal, vol 31, nº 5

Grant Promotes Diversity of State’s Linda University, University of the Pacific, recruitment and enrollment efforts, but Dental Work Force University of California at Los Angeles, also to review policies affecting dental edu- The California Endowment recently and University of Southern California. The cation and the attractiveness of the dental approved a $6.3 million grant to fund up to University of California at San Francisco profession to underrepresented students,” four California dental schools to increase School of Dentistry is one of the 11 schools Formicola said. the enrollment of minority and low- in the Robert Wood Johnson Foundation’s Bailit stated that “outreach by dental income students. The project also aims to $19 million “Dental Pipeline” project. schools to underserved communities has improve access to dental care for under- “It is critical for one of the nation’s a twofold purpose: It provides more care served populations through dental resident most diverse states to have an equally to disadvantaged patients and gives dental and student rotations in community clinics diverse health care work force. We are students and residents experience in caring and practices that provide care to disadvan- pleased to join forces with the Rob- for a diverse group of patients in commu- taged patients. ert Wood Johnson Foundation in this nity settings.” In 2000, less than 5 percent of Califor- important endeavor, and look forward to The Center for Community Health nia dental students were African-American, increasing the number of minority and Partnerships is a resource center than Hispanic, or Native American, and only low-income students enrolled in California enables physicians, dentists, nurses, and 8 percent of California dentists are from dental schools,” said Jai Lee Wong, senior public health professionals at Columbia these minority communities. Oral Health program officer for the Endowment. University to collaborate with community- in America: A Report of the Surgeon “What a tremendous opportunity for based organization on projects that reduce General pointed out the need to increase the California Endowment and the Robert health care disparities. the diversity of the dental workforce and Wood Johnson Foundation, to mesh our For more information about Pipeline, linked this to improving the health of individual philanthropic efforts into a Profession and Practice: Community-Based minority populations. focused area of concern,” added Judith Dental Education visit http://dentalpipe- California has 68 dental health profes- S. Stavisky, MPH, MEd, senior program line.columbia.edu. sional shortage areas, many in rural areas. officer at the Robert Wood Johnson Foun- The California Endowment was Along with financial and administrative dation. established in 1996 to expand access to limitations in public and private insurance The “Dental Pipeline” program office is affordable, quality health care for under- programs, these access problems are the based at Columbia University’s Center for served individuals and communities, and primary reasons for the low percentage of Community Health Partnerships under to promote fundamental improvements California Medi-Cal eligible children who the direction of Allan Formicola, DDS, in the health status of all Californians. visit the dentist. MS, at Columbia and Howard Bailit, DMD, The Endowment has regional offices in To address these workforce and ac- PhD, from the University of Connecticut Los Angeles, San Francisco, Sacramento, cess issues, California dental schools that Health Center and Hartford Hospital. Kim Fresno, and San Diego with staff working receive support from the Endowment will D’Abreu Herbert, MPH, also at Columbia, throughout the state. The Endowment participate in Pipeline, Profession & Prac- serves as the program’s deputy director. makes grants to organizations and institu- tice: Community-Based Dental Education, “Since there is such a limited pool of tions that directly benefit the health and a nationwide, 11-school initiative started by minority and low-income dental school well-being of the people of California. For the Robert Wood Johnson Foundation in applicants, it will be critical for all of the more information, visit their Web site at September 2002. Dental schools eligible to Dental Pipeline schools to work collabora- www.calendow.org apply for these $1.3 million grants are Loma tively; not only to increase their minority

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Link Found Between Perio Disease and professor of oral biology at the University tissue lesion (including canker sores, abra- Oral Lesions of Buffalo School of Dental Medicine. sions, redness, irritations, and general Dental researchers from the Univer- “Survival from oral cancer, as with sore spots) in the two groups. sity at Buffalo have found a significant most cancers, depends on the stage of Results showed that oral tumors were association between one measure of the disease at diagnosis. If further studies four times more prevalent and precancer- periodontal disease and oral precancerous demonstrate that periodontal disease ous lesions were twice as prevalent in lesions and tumors. is a significant risk and a warning sign, people with periodontal disease (as as- Analyzing data from the Third Na- screening and examinations for oral sessed by clinical attachment loss) than in tional Health and Nutrition Examination cancer can be targeted in order to improve those without periodontal disease. Survey, researchers found that people prevention and early detection of oral with serious periodontal disease were at cancer.” Researchers controlled for various double the risk of having a precancerous NHANES III was conducted in the conditions known to be risk factors for lesion and at four times the risk of having general U.S. population from 1988 to oral cancer, such as smoking, alcohol con- an oral tumor of any kind than people ’94 by the Centers for Disease Control sumption, age, gender, race, education, without serious gum disease. and Prevention. Physical examinations occupation, diet, and number of dental Results of the study were presented at of participants included an assessment visits. the American Association of Dental Re- of oral health, including the amount of “These findings suggest strongly that search meeting in San Antonio in March. clinical attachment loss, a measure of gum infection is associated with oral cancer,” “This is the first finding of a potential detachment from the underlying bone, Grossi said, “but they don’t prove that link between oral cancer and oral infec- and a standard indicator of periodontal oral infection is causally related to oral tion,” said Sara Grossi, DDS, a co-author disease. cancer. If clinical studies prove that to be on the study, “but there is evidence of an For this study, people in the NHANES true, the implications for public health infection link in other cancers.” She noted III database who were at least 20 years old would be tremendous. Additional research research showing an association between and had a minimum of six natural teeth -- in this area could significantly improve Helicobacter pylori and stomach can- a total of 13,798 -- were placed into one of oral-cancer screening and early detection cer, human papillomavirus and cervical two groups based on clinical attachment programs, and help reduce mortality from cancer, and cytomegalovirus and Kaposi’s loss: less or more than an average of 1.5 oral cancer.” sarcoma. mm for all teeth.. “The potential implications of this as- Researchers then determined the pres- sociation of gum disease and oral cancer is ence of oral tumors (any unusual growth), enormous,” said Grossi, clinical assistant precancerous lesions, or any kind of soft

On the Cover

The First Operation Under Ether (detail) Robert C. Hinckley The First Operation Under Ether, an oil on canvas by Robert C. Hinckley (1853-1940), depicts the introduction of anesthesia into surgery. It is actually an amalgamation of the three operations that were required to convince the medical community of Boston that painless surgery was possible. The painting, known worldwide as one of the best depictions of a surgical operation, shows actual surgeons who attended at least one of the three surgeries, though not necessarily the first. The painting was completed in 1894 and acquired by the Boston Medical Library in 1903. Used with permission of the Boston Medical Library in the Francis A. Countway Library of MedicineInformation on OSAP conferences, newsletters, training programs, and other C.E. offerings is available at www.osap.org.

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Bilingual Helpline Connects Hispanic Audiologists Say Dental Staff May Treatment Acceptance Hinges on Rela- Families With Health Services Need Hearing Protection tionship With Patient A new bilingual health helpline has Recent clinical experience and related Dentists need to understand more been opened to help Hispanic families research reveal that dentistry may be an about the total care of patients, addressing get basic health information to help them at-risk profession for hearing loss, wrote not only their physical needs but also their prevent and manage chronic conditions, audiologists at the Medical College of emotional or psychological needs, wrote and to refer them to local health provid- Georgia in an article in the December Cathy Jameson, PhD, in Dental Practice ers and federally supported programs. 2002 GDA Action, journal of the Georgia Management, winter 2002 edition. The National Hispanic Family Health Dental Association. The days of telling a person what they Helpline Su Familia, (866) 783-2645 or They noted that dentists and their need and having them immediately accept (866) SU-FAMILIA, is open Monday staffs have joined the ranks of others who have come to an end, Jameson wrote. through Friday, 9 a.m. to 6 p.m. Eastern are vulnerable to hearing loss: rock musi- Informed patients want to participate in Time. It was developed and is operated by cians, railroad and construction workers, treatment planning and decision making. the National Alliance for Hispanic Health and military personnel. She stressed that each person on the den- and is supported by the U.S. Department According to the National Institute for tal team plays a significant role in making of Health and Human Services’ Health Occupational Safety and Health, noise- effective presentations. Resources and Services Administration induced hearing loss is the most common Case presentations provide the chal- and Office of Minority Health. occupational injury, the researchers write. lenge of educating and motivating people. “Hispanics continue to face health The majority of the recent studies suggest Jameson said the purpose of the consulta- disparities. This is unacceptable,” Health that the noise levels experienced by the tion is to make it possible for patients to and Human Services Secretary Tommy dental team have the potential to result go ahead with the dental treatment. G. Thompson said. “That’s why we are in hearing loss and/or tinnitus (ringing Jameson says there are six steps in a committed to getting information and re- or buzzing in the ears) for dentists and successful case presentation: sources to those communities where the their staff who work with high-speed air * Build the relationship. Confidence health gap exists. By establishing the Su turbine handpieces. and trust must first be established before Familia helpline, we are helping families The articles cited one survey of Cali- people will accept a service get access to the best health information.” fornia dentists that showed that every * Establish the need. To establish Su Familia bilingual information dentist who had purchased a high-speed the need, careful and caring listening is specialists are able to refer callers to one handpiece also had some measurable required to understand how patients feel of more than 16,000 local health provid- degree of hearing loss, and that over half about their dental needs. ers, including community and migrant experienced moderate to severe tinnitus. * Educate and motivate. These are ongo- health centers, by using the callers’ zip The researchers noted that loud noise ing but are most critical at the time of the code. Callers can also request basic health levels in the dental environment can consultation. information, referrals to information also affect patients. For some patients, * Ask for a commitment. Jameson said sources, or receive consumer-friendly, the high noise levels can add to overall it is necessary to ask for a commitment bilingual Su Familia fact sheets. Fact anxiety. Patients with sensorineural or people can walk out without deciding. sheets are available for a wide variety of hearing loss often experience an acoustic Asking for a commitment also determines topics including , cancer screening, phenomenon known as “recruitment,” an whether patients have any objections or cardiovascular disease, child and adult im- abnormal perceptual increase in loudness barriers. munizations, diabetes, domestic violence, due to the hearing loss. These patients, * Make a financial arrangement. This and HIV/AIDS. the authors said, may be extremely sensi- should be done before scheduling appoint- tive to even moderately loud sounds. ments, Jameson said. The audiologists suggest that hearing * Schedule appointments. protection and conservation needs to Jameson said that dentists who follow become a regular part of dental office pro- this six-step process of case presentation tocol, especially for those directly exposed will find acceptance rates will increase. to noise-generating equipment.

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Bilingual Helpline Connects Hispanic Families With Health Services A new bilingual health helpline has been opened to help Hispanic families get basic health information to help them prevent and manage chronic conditions, and to refer them to local health providers and federally supported programs. The National Hispanic Family Health Helpline Su Familia, (866) 783-2645 or (866) SU-FAMILIA, is open Monday through Friday, 9 a.m. to 6 p.m. Eastern Time. It was developed and is operated by the National Alliance for Hispanic Health and is supported by the U.S. Department of Health and Human Services’ Health Resources and Services Administration and Office of Minority Health. “Hispanics continue to face health disparities. This is unacceptable,” Health and Human Services Secretary Tommy G. Thompson said. “That’s why we are committed to getting information and resources to those communities where the health gap exists. By establishing the Su Familia helpline, we are helping families get access to the best health information.” Su Familia bilingual information specialists are able to refer callers to one of more than 16,000 local health providers, including community and migrant health centers, by using the callers’ zip code. Callers can also request basic health information, referrals to information sources, or receive consumer-friendly, bilingual Su Familia fact sheets. Fact sheets are available for a wide variety of topics including asthma, cancer screening, cardiovascular disease, child and adult immunizations, diabetes, domestic violence, and HIV/AIDS.

Audiologists Say Dental Staff May levels in the dental environment can also Case presentations provide the chal- Need Hearing Protection affect patients. For some patients, the lenge of educating and motivating people. Recent clinical experience and related high noise levels can add to overall anxiety. Jameson said the purpose of the consulta- research reveal that dentistry may be an Patients with sensorineural hearing loss tion is to make it possible for patients to at-risk profession for hearing loss, wrote often experience an acoustic phenomenon go ahead with the dental treatment. audiologists at the Medical College of known as “recruitment,” an abnormal Jameson says there are six steps in a Georgia in an article in the December 2002 perceptual increase in loudness due to the successful case presentation: GDA Action, journal of the Georgia Dental hearing loss. These patients, the authors * Build the relationship. Confidence Association. said, may be extremely sensitive to even and trust must first be established before They noted that dentists and their moderately loud sounds. people will accept a service staffs have joined the ranks of others who The audiologists suggest that hearing * Establish the need. To establish are vulnerable to hearing loss: rock musi- protection and conservation needs to the need, careful and caring listening is cians, railroad and construction workers, become a regular part of dental office pro- required to understand how patients feel and military personnel. tocol, especially for those directly exposed about their dental needs. According to the National Institute for to noise-generating equipment. * Educate and motivate. These are ongo- Occupational Safety and Health, noise- ing but are most critical at the time of the induced hearing loss is the most common Treatment Acceptance Hinges on Rela- consultation. occupational injury, the researchers write. tionship With Patient * Ask for a commitment. Jameson said The majority of the recent studies suggest Dentists need to understand more it is necessary to ask for a commitment that the noise levels experienced by the about the total care of patients, addressing or people can walk out without deciding. dental team have the potential to result not only their physical needs but also their Asking for a commitment also determines in hearing loss and/or tinnitus (ringing or emotional or psychological needs, wrote whether patients have any objections or buzzing in the ears) for dentists and their Cathy Jameson, PhD, in Dental Practice barriers. staff who work with high-speed air turbine Management, winter 2002 edition. * Make a financial arrangement. This handpieces. The days of telling a person what they should be done before scheduling appoint- The articles cited one survey of Califor- need and having them immediately accept ments, Jameson said. nia dentists that showed that every dentist have come to an end, Jameson wrote. * Schedule appointments. who had purchased a high-speed hand- Informed patients want to participate in Jameson said that dentists who follow piece also had some measurable degree treatment planning and decision making. this six-step process of case presentation of hearing loss, and that over half experi- She stressed that each person on the den- will find acceptance rates will increase. enced moderate to severe tinnitus. tal team plays a significant role in making The researchers noted that loud noise effective presentations.

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Tooth Loss Can Be Emotional Experi- Hygienists Speak up on What Makes ence for Some Patients Them Stay at Their Jobs A study by Canadian researchers found Dental staff members who think their that 53 percent of partially dentate people employers are fair and generous are hap- found it difficult to come to terms with pier than those who don’t, wrote Janyce their tooth loss, according to an article in Hamilton in the January/February 2003 the November 2002 Oral Health. CDS Review, journal of the Chicago Dental The study investigated the reactions Society. And, Hamilton added, when staff to tooth loss in a partially dentate group is happy, retention and recruitment is not of 100 people using a questionnaire-based a problem. study. Hamilton’s article detailed the respons- The researchers found that partially es from hygienists across the country who dentate people who experienced difficul- were asked: What do dentists have to do ties in accepting their tooth loss were more to make their staff happy? The responses likely than those who had no difficulties came in the form of first-hand stories to feel less confident, restrict food choice, of what the hygienists love about their enjoy food less, avoid laughing in public, employers. and avoid forming close relationships. In their responses, the hygienists noted Of the 100 people in the study, 91 com- many reasons for liking their employers, pleted the questionnaire, 38 men and 53 including: women. In 78 percent of the cases, people * Excellent pay; had missing anterior teeth and 22 percent * Better-than-average benefits; had only posterior teeth missing. Of the * Easy to talk to; participants, 81 were wearing partial den- * Pride in their work and compassion for tures and 10 were in the process of having patients; and their first partial dentures constructed. * Day-to-day kindness and mutual When asked if they found it difficult to respect. accept losing teeth, 53 percent reported dif- Hamilton wrote that many of those ficulty accepting tooth loss and 41 percent who responded to the survey noted that said they had no difficulty accepting it. small things matter. Little kindnesses do The overriding emotion felt by those who not go unnoticed, according to many of had no difficulty in accepting the loss of the respondents. their teeth was one of relief. People who experienced difficulties expressed a wider and more complex range of emotions. The most common were sadness, depression, and feeling old. The researchers also found that 51 percent of those who experienced difficul- ties with tooth loss felt that they had been unprepared for the effects that tooth loss had on them. Those people said that an explanation from the dentist would have helped.

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Pain and Anxiety Control in Dentistry — This Is No Humbug

Tim Silegy, DDS

Contributing ain and suffering are an unfortunate part of Editor human experience. It is also perhaps den- other health professionals do. Dr. Alan Budenz reviews tistry’s greatest paradox. basic concepts of , introduces new Tim Silegy, DDS, is a diplomate of the Patients will refrain from seeing the agents and armamentaria, and gives protocols for man- American Board of dentist for years fearing the relatively minor aging the hard-to-numb patient. Oral and Maxillofacial Pdiscomfort of the dental injection. They will reject even * Drs. Stanley Malamed and Morris Clark review Surgery. He maintains a the simplest of treatment plans stating, “If my tooth nitrous oxide and address myths that may be prevent- private practice in Long doesn’t hurt, Doc, why bother?” ing its more frequent use. They make the case that with Beach, Calif Paradoxically, the pain of a toothache (avoidable proper administration and well-maintained equipment, with regular preventive care) is frequently what drives the nitrous oxide-oxygen technique has an extremely our patients to see us. high success rate and a very low rate of adverse effects. For many, “pain” and “dentistry” are synonymous, * Dr. Roger Kingston and I discuss the principal so much so that this association has been incorporated pharmacologic modalities that appropriately trained into our popular vernacular. dentists can use to manage pain and anxiety in appre- A daunting task is “like pulling teeth,” a difficult hensive dental patients. decision, akin to a root canal. * Dr. Scott Jacks and I review oral conscious seda- John Patrick’s play The Teahouse of the August tion and demonstrate that it can be a safe and cost- Moon chronicles the struggles of Okinawan villagers effective alternative to intravenous sedation and general during the Second World War. The play ends with the anesthesia for children who could otherwise not be protagonist making this statement. “Pain makes man treated. think. Thought makes man wise. Wisdom makes life * Dr. John Yagiela challenges traditional assump- endurable.” tions about the appropriate management of acute and I saw the play almost 20 years ago, and this closing postoperative dental pain by reviewing the literature on statement has stayed with me ever since. currently available oral analgesics used in dentistry. I am reminded of it almost daily, as I induce general * Patients suffering from chronic pain and headache anesthesia in an apprehensive patient for third-molar can be found in all dental practices. Dr. Steven Graf- removal, see the look of relief in the eyes of a tooth- Radford reviews current methods of diagnosing chronic ache patient after having received a mandibular block, pain and discusses the physical, pharmacologic, and witness the blank stare of a pediatric patient breathing behavioral interventions currently used to manage it. nitrous oxide who was crying only moments before, or The work of these individuals reflects dentistry’s explain to a patient with facial pain that in spite of what ongoing commitment to reducing and, it is hoped, one others may think her pain is real and she is not crazy. day eliminating pain and anxiety in our patients. As dentists, we are judged not by our ability to carve It is a noble cause now, as it was 150 years ago when, tertiary anatomy into a shiny new amalgam, but rather in amazement, Dr. John Warren uttered, “Gentlemen, by our ability to make the procedure painless. this is no humbug!” after having painlessly removed a It is appropriate, then, that we dedicate this issue of tumor from a patient under the effects of ether anesthe- the Journal of the California Dental Association to pain sia administered by, none other than a dentist, William and anxiety control in dentistry. T.G. Morton, DDS. * Dentists utilize local anesthesia more than any

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Local Anesthetics in Dentistry: Then and Now

Alan W. Budenz, MS, DDS, MBA abstract Local anesthetics have been in use in dental practice for more than 100 years. The advent of local anesthetics with the development of nerve blockade injection techniques heralded a new era of patient comfort while permitting more extensive and invasive dental procedures. A brief history and summary of the current local anesthetics available in the United States is provided, and some of the newest techniques for delivering local anesthetics are reviewed. General guidelines for addressing difficulties encountered in anesthetizing patients are also discussed.

authors

Alan W. Budenz, MS, he first agent first operation using local anesthesia DDS, MBA, is an associate to be widely used in dentistry induced by topical cocaine on a patient professor of anatomy and chair of the was cocaine. Centuries before undergoing glaucoma correction.2 The Department of Diagnosis European exploration of the noted American surgeon William Halsted and Management at the New World, Peruvian Indians was the first person to inject cocaine for University of the Pacific Thad found that chewing leaves of the coca nerve conduction blockade, performing School of Dentistry in plant produced exhilaration and relief infraorbital and San Francisco. from fatigue and hunger. Following the blocks for dental procedures in November import of coca leaves to Europe, much 1884.3 Halsted subsequently developed research was conducted to elucidate numerous other regional the properties of the coca leaf extract. injection techniques, many of which are In 1859, Albert Niemann refined the still fundamental to dental practice. coca extract to the pure alkaloid form Despite its promise for pain manage- and named this new drug “cocaine.” ment during surgery, cocaine had major Niemann recognized the anesthetic drawbacks, such as a high propensity for effect of cocaine when he noted that addiction and a short duration of action. “it benumbs the nerves of the , The latter factor necessitated injection depriving it of feeling and taste.”1 In the of large doses of the drug, increasing the summer of 1884, Carl Koller, a junior potential for severe systemic toxicity. One resident in the University of Vienna technique developed to counteract this Ophthalmological Clinic, conducted short duration/high dose problem was experiments to test the to apply a tourniquet near the opera- properties of cocaine on the corneas tive site. In addition to the risk of local of various lab animals and on himself tissue damage, this approach had limited (self-administration being common in success in many regions of the body and medical research at that time). He found was impractical for anesthesia of the oral that the drug rendered the corneas cavity. In 1903, Heinrich Braun reported insensitive to pain. In September of that epinephrine could be used as a that year, Koller performed the world’s “chemical tourniquet” when added to a

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solution of cocaine by producing local- developed for use in dental procedures: number of factors:7 ized vasoconstriction to slow the rate of , , , * Individual variation in response to vascular uptake, and thus reducing the etidocaine, and . The advantages the drug administered; required dose of cocaine.4 However, the of the amide-based anesthetic agents, par- * Accuracy in administration of the drawbacks of cocaine were still significant, ticularly their very low rate of allergenicity drug; and research to find a synthetic substitute as compared to the ester-type anesthetics, * Status of the tissues at the site of was widely undertaken. In 1905, Alfred led to their gradual and complete replace- drug deposition (vascularity, pH); Einhorn and his associates in Munich ment of the ester-based anesthetics in * Anatomical variation; and reported their discovery of , an dental use. The last ester anesthetics pack- * Type of injection administered ester-based synthetic local anesthetic.5 aged in a dental cartridge were (supraperiosteal [“infiltration”] or nerve Procaine was immediately accepted as a discontinued in the mid-1990s. block). safe substitute for cocaine. Some histori- ans consider the discovery of procaine to Current Dental Anesthetic Agents mark the beginning of the modern era of Today’s availability of a variety of Lidocaine is considered the proto- regional anesthesia. Several other ester- local anesthetic agents enables dentists typical amide anesthetic agent. At its type local anesthetics were subsequently to select an anesthetic that possesses introduction in 1948, it was roughly twice developed and remained in wide use in specific properties such as time of onset as potent and twice as toxic as procaine, the United States throughout most of the and duration, hemostatic control, and producing a greater depth of anesthesia 20th century. degree of cardiac side effects that are ap- with a longer duration over a larger area In 1943, Nils Löfgren, a Swedish chem- propriate for each individual patient and than a comparable volume of procaine. ist, synthesized a new amide-based local for each specific dental procedure. Table Consequently, lidocaine quickly became anesthetic agent, derived from xylidine, 1 lists the anesthetic agents available for the most popular local anesthetic in den- and named it “lidocaine.”6 Lidocaine was dental use in the United States and briefly tistry. It is available in the United States more potent and less allergenic than pro- summarizes their properties. It should be in three formulations: 2 percent without caine and the other ester-based anesthet- noted that these properties, particularly vasoconstrictor (plain), 2 percent with ics. Since Löfgren’s discovery of lidocaine, duration and depth of anesthesia, are only 1:100,000 epinephrine vasoconstrictor, several other amide anesthetics have been approximations and are variable due to a and 2 percent with 1:50,000 epinephrine.

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Lidocaine without vasoconstrictor has a a potential new producer of levonordefrin that chemical toxicity may be the cause soft-tissue anesthetic duration of one to is currently running production tests and of these increased paresthesias since the two hours, but a pulpal duration of only may have mepivacaine with levonordefrin only common feature of prilocaine and five to 10 minutes and is therefore of back on the U.S. market by mid to late articaine is that they are both 4 percent limited use for most dental procedures. 2003.11 concentration anesthetic agents.14 His Both formulations with the epinephrine hypothesis is supported by reports of vasoconstrictor have a pulpal duration of Prilocaine neurologic deficits with 4 percent lido- one to 1.5 hours and a soft-tissue range of Prilocaine, also introduced in 1960, caine in animal studies15 and in human three to five hours. The 1:50,000 epineph- is slightly less potent and considerably studies using 5 percent lidocaine for spinal rine concentration may be advantageous less toxic than lidocaine as a local anes- anesthesia.16-18 This suggests that reduc- for hemostasis in surgical sites but has thetic agent. Like mepivacaine, prilocaine tion of dosage to the absolute minimum no significant advantage for duration of produces less tissue vasodilation than amount required for effective anesthesia pulpal anesthesia. lidocaine and can be used reliably in plain and the use of a slow, atraumatic injec- solution form for short-duration proce- tion technique with repeated aspirations Mepivacaine dures. Prilocaine is available as a 4 percent are wise precautions if either of these Introduced in 1960, a 2 percent solu- plain solution or as a 4 percent solution anesthetic agents is selected for use with tion of mepivacaine has potency and with 1:200,000 epinephrine. The plain inferior alveolar and block toxicity ratings roughly equivalent to a 2 solution has a pulpal duration of 40 to 60 injection techniques at all. percent solution of lidocaine. The greatest minutes with soft-tissue anesthesia for Bupivacaine advantage of mepivacaine is that it has two to three hours. It is worth noting that Bupivacaine is an analogue of mepi- less vasodilating activity than lidocaine the duration of anesthesia with plain pri- vacaine that exhibits a fourfold increase (all anesthetic agents without an added locaine is more dependent upon the type in potency and toxicity and a remarkable vasoconstrictor are vasodilators to some of injection given than are other anesthet- increase in the duration of anesthesia. degree) and can therefore be used reli- ics. Infiltration injections of prilocaine Released in the United States in 1983 and ably as a nonvasoconstrictor-containing plain may only provide five to 10 minutes available only as a 0.5 percent solution solution for procedures of short dura- of pulpal anesthesia while regional block with 1:200,000 epinephrine, bupivacaine tion.7 Mepivacaine is available on the U.S. injections typically show the commonly may exhibit a slightly slower time of onset market as either a 3 percent plain solution described 40- to 60-minute durations. in some patients, approximately six to or a 2 percent solution with 1:20,000 levo- The vasoconstrictor-containing solution 10 minutes compared with two to seven nordefrin. The plain solution has a pulpal provides pulpal anesthesia for one to 1.5 minutes for lidocaine and mepivacaine.4 anesthetic duration of 20 to 40 minutes hours like lidocaine and mepivacaine with The longer duration of anesthesia for with a soft-tissue duration of two to three a potentially longer soft-tissue duration which bupivacaine is known is achieved hours. The vasoconstrictor-containing of three to eight hours.7 Anecdotally, primarily via regional nerve block injec- solution has a pulpal duration equivalent prilocaine has been said to have greater ef- tion techniques with mandibular blocks to that of lidocaine with vasoconstrictor, ficacy in patients who are difficult to anes- frequently having greater duration than that is, pulpal anesthesia for one to 1.5 thetize, for example, patients with a past maxillary blocks. As a block, pulpal dura- hours and soft-tissue duration of three or present history of substance abuse. tions of 1.5 to seven hours are common to five hours. It should be noted that An additional advantage is the decrease with soft-tissue anesthesia of five to 12 although the levonordefrin vasoconstric- in cardiac side effects due to the lower hours. When administered via infiltration tor in mepivacaine is less likely to produce vasoconstrictor concentration. Relative technique, bupivacaine provides anesthet- cardiac side effects, such as palpitations, contraindications for the use of prilocaine ic depth and duration comparable to other than is epinephrine, it is more likely to include a patient history of methemoglo- local anesthetic agents. increase blood pressure and does have binemia, anemia, or cardiac or respiratory Etidocaine a higher potential for interaction with failure due to hypoxia.7 This long-acting amide anesthetic has tricyclic antidepressants such as amitrip- An additional precaution is raised been discontinued in the North American tyline hydrochloride.8-10 At the time of by reports of a significantly increased market. this writing, levonordefrin production has risk of nerve paresthesia with the use of Articaine been discontinued in the United States prilocaine and articaine, particularly for Articaine is an analogue of prilocaine and existing supplies of mepivacaine inferior alveolar and lingual nerve block in which the benzene ring moiety found with levonordefrin are expected to be injections.12,13 Haas, the lead author of a in all other amide local anesthetics has exhausted by early to mid-2003. However, number of these studies, has speculated been replaced with a thiophene ring. Al-

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though not released in the United States until April 2000, articaine has been avail- able in Germany since 1976 and in Canada since 1983 in a number of formulations. To date, only one formulation has been approved in the United States, a 4 percent solution with 1:100,000 epinephrine. With a higher per-cartridge unit cost and a pulpal anesthesia duration of approxi- mately one hour with soft-tissue anesthe- sia for two to four hours, it would initially appear that articaine is a less attractive agent for dental applications. However, with a slightly faster onset of action (1.4 to 3.6 minutes19), reports of a longer and perhaps more profound level of anes- thesia,20,21 and most notably frequent practitioner anecdotes of a greater ability more variable innervation pathways,22-29 systems are particularly adept at eliminat- to diffuse through tissues, articaine has more problems of inadequate anesthesia ing, or at least minimizing, the discomfort become a very widely used anesthetic in occur in the mandibular arch than in the of palatal injections.31-33 Such systems the European and Canadian markets. The maxillary. Although failures are more are discussed in greater detail under New tissue diffusion characteristics of articaine common in the mandibular arch, maxil- Delivery Systems and Techniques. are not well-understood; however, in a lary failures do occur and can be equally variable percentage of patients, a maxil- frustrating. The lary infiltration injection in the buccal Problems with mandibular anesthesia vestibule will result in adequate palatal The Maxilla are most common in the molar region anesthesia for tooth extraction. Similar Most problems with maxillary an- but are by no means limited to these results have been claimed for the man- esthesia can be attributed to individual teeth.23-29,34 As in the maxilla, most dibular anterior and premolar teeth with variances of normal anatomical nerve anesthesia problems encountered in the buccal infiltrations.19 As discussed with pathways through the maxillary bone mandible are due to individual variations prilocaine, reports of a significantly in- (Table 2).30 While the pulpal sensory in the nerve pathways, in other words, creased risk of nerve paresthesia with the fibers of the maxillary teeth are primar- accessory innervation (Table 2).34,35 use of articaine and prilocaine, particu- ily carried in the anterior, middle, and The first, and simplest, guideline re- larly for inferior alveolar and lingual nerve posterior superior alveolar nerves, which lates to the extent of anesthesia achieved. block injections,12,13 warrants practitio- also supply the buccal soft tissues, ac- If, for example, a patient reports profound ner caution in the use of these anesthetic cessory pulpal innervation fibers may be anesthesia of his or her lower and agents. found in the palatal innervation supplied tongue after receiving an inferior alveolar The Difficult-to-Anesthetize Patient by the nasopalatine and greater palatine and lingual nerve block injection, but Many factors may affect the success of nerves.30 By careful application of topical the tooth in question is still sensitive, it local anesthesia, some within the prac- anesthetics, distraction techniques (ap- is probable that those two nerves have titioner’s control and some clearly not. plication of pressure and/or vibration), been successfully anesthetized and that While no single technique will be success- and slow delivery of the anesthetic agent, the tooth sensitivity is very likely due to ful for every patient, guidelines exist that palatal injections can be given with very accessory innervation. This conclusion can help reduce the incidence of failure. little to no patient discomfort. With the is based upon nerve morphology. Fibers For this discussion, a failure will be availability of articaine hydrochloride 4 near the periphery of a nerve bundle defined as inadequate depth and/or dura- percent with epinephrine in the United tend to innervate the most proximal tion of anesthesia to begin or to continue States, many practitioners are finding that structures, i.e., molars in the case of the a dental procedure. Due to a number of palatal injections may not be necessary inferior alveolar nerve; while fibers in factors, such as thicker cortical plates; a when it is injected into the maxillary the center of the nerve bundle tend to denser trabecular pattern; larger, more buccal vestibule.20 Additionally, new innervate the most distal structures, i.e., myelin(lipid)-rich nerve bundles; and computer-controlled anesthetic delivery the incisors in this example.7 If a patient

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reports that his or her lower lip and the mylohyoid nerve has been clearly shown tip of his or her tongue are anesthetized, to carry sensory fibers to mandibular structures that are innervated by the most teeth.28,39 A mylohyoid nerve block may central fibers of the inferior alveolar and be delivered by injecting into the floor of lingual nerve bundles respectively, than it the mouth between the medial surface seems reasonable to conclude that these of the mandible and the sublingual fold two nerves are indeed anesthetized and formed by the sublingual salivary gland. that accessory innervation to the sensitive The injection should be given just distal tooth likely exists in this patient. to the sensitive tooth, and the depth of For mandibular molars, a common, the injection should approximate the and therefore important, accessory root apices.41 An alternative technique pathway to be considered is the long to anesthetize the mylohyoid nerve is buccal nerve.27,36-38 This nerve branches to administer a second inferior alveolar from the anterior division of the man- nerve block at a higher and/or deeper dibular portion of the trigeminal nerve site.34 This may better approximate high within the infratemporal fossa and the origin of the mylohyoid nerve as it using a different anesthetic agent for crosses the anterior border of the man- branches from the inferior alveolar nerve, the second injection may increase the dibular ramus above the retromolar pad but this technique does carry an increased likelihood of successful duration. This to enter and innervate the mucosa and risk of intravascular injection and possible difference may be explained by individual overlying skin of the cheek, including the hematoma.35,42 variances in tissue pH conditions and mandibular buccal attached gingiva. Due A potentially more efficient method differing characteristics of each anesthetic to the possible branching of this nerve as for dealing with accessory innervations agent, such as dissociation characteristics, it descends along the medial surface of in the mandible is to use a more com- lipid solubilities, and receptor site protein- the mandibular ramus, a high injection plete mandibular block technique such as binding affinities. No contraindication -ex site along the long buccal nerve pathway the Gow-Gates43 or Vazirani-Akinosi44 ists for using any of the amide anesthetic may offer a greater likelihood of success- techniques (Table 3). These injections, agents in combination with one another; fully anesthetizing more of these acces- first described in the early 1970s, are given however, care must be taken to limit the sory branches.26 Such a site for blocking at higher sites on the mandibular ramus total dosage of anesthetic given to the the long buccal nerve is to inject into the (Figure 1) and are aligned relative to the maximum amount allowable for the agent soft tissue just medial to the anterior maxillary occlusal plane rather than the with the lowest permissible dosage. For border of the ramus at or above the same mandibular. Properly performed, these all injections given, the precise amount of level above the mandibular occlusal plane techniques have a very high success rate each agent injected and the specific site of as the inferior alveolar block injection is coupled with a very low risk of positive each injection should be recorded in the given, i.e., using the depth of the coro- vascular aspiration.45 It should be noted, patient’s treatment record. It is particu- noid notch anteriorly as the landmark however, that even a high mandibular di- larly helpful to note if one agent appears for the horizontal level of the injection.4 vision nerve block technique, such as the to have worked better than another. In An added benefit of this site is improved Gow-Gates, may not have a 100 percent these cases, this “better” agent should be patient comfort by injecting medial to the success rate in anesthetizing all possible used for the first injection at the next ap- anterior border of the mandible rather nerve branches to mandibular tooth pointment. than into the lateral tissue. pulpal tissues.46,47 For this reason, the An additional source of accessory in- best advice is to be proficient with a vari- The “Hot” Tooth nervation to any mandibular tooth is the ety of mandibular injection techniques as Anesthetizing the “hot” tooth, a condi- mylohyoid nerve.23-25,28,39 This nerve described in detail in the dental literature. tion generally indicating an irreversible arises from the inferior alveolar nerve Another concern is the situation pulpitis, can be one of the most frustrat- at a variable level above the mandibular where anesthesia of all apparent nerve ing problems for any dental practitioner. foramen and may not be consistently pathways is achieved, but the duration is Whenever possible, prescribing antibiotic anesthetized with a conventional inferior short and/or the depth of anesthesia is therapy to reduce inflammation and allow- alveolar block injection.40 Although it is poor. Giving a second injection into the ing the site to settle down may constitute anatomically described as a motor nerve same site as the first injection may prove the best course of action. When such a innervating both the mylohyoid and the adequate simply due to the increased course is not an option, the first step in anterior belly of the digastric muscles, the volume of anesthetic solution. However, working through this situation is to de-

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liver an appropriate nerve block injection system include the initial cost of the unit, delivery rate of anesthetic solution for a as far back as possible along the innerva- approximately $1,400; the cost of the selection of injection techniques (block, tion pathway of the hypersensitive tooth. disposable syringe/handpiece assembly infiltration, palate, PDL, intraosseous) If all of the surrounding soft tissues are per patient, approximately $1; the longer/ preselected by the operator. Although numb, but the tooth itself is still sensitive, slower injection time; and, due to the vol- bulkier than the Wand syringe/handpiece, use of an intraosseous technique, which ume of the tubing connecting the motor the Comfort Control Syringe also en- has a highly predictable success rate, is unit to the handpiece, only 1.4 ml of an- ables the operator to use a pen grip while recommended.48-50 Less predictable, but esthetic solution can actually be delivered injecting. The Comfort Control Syringe also potentially effective, is a periodontal from each anesthetic cartridge.57 Ad- houses the anesthetic cartridge directly ligament injection technique.51-53 A last ditionally, the system does require some behind the needle, just as in a traditional resort is to quickly access a pulp horn, time to get accustomed to: The system is syringe; and the injection controls are creating a hole just large enough to insert operated by a foot-pedal control, and the fingertip accessible on the syringe rather a needle, and injecting anesthetic directly anesthetic cartridge is not directly visible than via foot pedal. The initial unit cost is into the pulp chamber of the tooth. The in the operator’s hand. This latter factor approximately $900 with disposable sup- major limitation of all three of these injec- is addressed by a series of audible sounds plies costing approximately 55 cents per tion techniques is the inability to anes- that inform the operator of how much patient.58-61 thetize multiple teeth with a single needle anesthetic solution has been delivered. Although the technique of delivering penetration and the relatively short dura- Introduction of the Wand delivery local anesthetics directly into alveolar tion of anesthesia achieved.53,54 system has renewed interest in the palatal bone in close proximity to root apices is approach to anesthesia of the anterior not new, recent technology has greatly New Delivery Systems and Techniques and middle superior alveolar nerves.58,59 improved the convenience of intraos- In the past decade, two delivery Using the palatal approach, anesthesia of seous injections. Systems marketed by systems have been developed that utilize the pulpal tissues of the maxillary incisor Stabident, X-tip, and Intraflow have been computer technology in the administra- and premolar teeth, as well as anesthesia incorporated into many dental practices. tion of local anesthetics to patients. The of the buccal and palatal gingival tissues, The intraosseous technique is quite Wand (Milestone Scientific) and the may be accomplished without the side reliable for pulpal anesthesia for one or Comfort Control Syringe (Dentsply) both effect of facial anesthesia found with the two teeth and is particularly useful for recognize that the more slowly an injec- infraorbital nerve approach. Preservation anesthetizing the “hot tooth.” Primary tion is given, the less traumatic it is to the of normal facial sensation and movement pulpal anesthesia using an intraosseous tissues of the injection site and therefore is an advantage for mid-procedure smile technique is effective in 45 percent to 93 the more comfortable the injection is to line assessment of maxillary anterior percent of cases with short duration of the patient. The Wand precisely controls cosmetic procedures, and patient accep- approximately 30 minutes.54 When used the flow rate and modulates fluid pressure tance is an additional advantage. On a as a supplement to an inadequate conven- by use of a computer microprocessor and precautionary note, it is imperative that tional infiltration or nerve block injection, an electronically controlled motor to de- this injection be administered very slowly the intraosseous technique is effective liver the anesthetic solution at a slow rate with constant visual by the in 80 percent to 90 percent of cases with regardless of tissue resistance.55 This al- operator to avoid excessive tissue blanch- profound anesthesia of moderate duration lows the operator to deliver the anesthetic ing. The recommended injected volume is (60 to 90 minutes).54 solution into any injection site, including 0.6 to 0.9 ml administered over a 60- to Intraosseous injections require a the palate, at a rate that is potentially 90-second, or longer, interval. If excessive system for penetrating the cortical plate below the threshold of pain. An additional tissue blanching is observed during the of bone so that the anesthetic agent may advantage is the smaller diameter of the injection, a momentary pause to allow be injected into the cancellous tissue syringe/handpiece itself, which permits return of normal blood supply, indicated space from where it then diffuses to the the operator to use a more comfort- by return of pink coloration to the tissue, desired root apices. The Stabident System able and stable pen grip on the syringe, is recommended. A risk of palatal tissue (Fairfax Dental) is a two-part system with allowing for more natural use of finger ulceration must be recognized if marked a separate perforator needle that mounts rests while injecting. The smaller size of ischemia occurs.58,59 to a low-speed handpiece. The anesthetic the syringe may also be less intimidating The Comfort Control Syringe is a new- injection needle is then passed through to patients, a significant consideration er entry in the electronic, computer-con- the perforation into the cancellous bone. when working with a dental-phobic pa- trolled anesthetic delivery system market. One cause of difficulty with this system tient.33,56-58 Disadvantages of the Wand This preprogrammed unit controls the is the necessity of aligning the injection

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22. Carter RB, Keen EN, The intramandibular course of the needle precisely with the perforation Summary inferior alveolar nerve. J Anat 108:433-40, 1971. channel to gain access to the cancellous What might be next on the front for 23. Rood JP, The nerve supply of the mandibular incisor region. Br Dent J 143:227-30, 1977. space. This problem has been addressed in dental anesthesia? As dental lasers con- 24. Frommer J, Mele FA, Monroe CW, The possible role of the the Stabident System by adding a funnel- tinue to evolve and become increasingly mylohyoid nerve in mandibular posterior tooth innervation. J shaped needle guide that is inserted into refined, they may yet reach their early Am Dent Assoc 85(1):113-7, 1972. 25. Madeira MC, Percinoto C, Silva MGM, Clinical significance the perforation channel. The X-Tip System promise of providing “painless dentistry of supplementary innervation of the lower incisor teeth: a (X-Tip Technologies) has also addressed without the needle or the drill.” Such an dissection study of the mylohyoid nerve. O Surg O Med O this problem in its system design. The event will surely usher in a new era of Pathol 46:608-14, 1978. 26. Sutton RN, The practical significance of mandibular X-Tip is also a two-part system, similar patient comfort, potentially decreasing accessory foramina. Aust Dent J 19:167-73, 1974. to the Stabident, with the exception that the number of dental-phobic patients. The 27. Haveman CW, Tebo HG, Posterior accessory foramina of removal of the perforator needle leaves a prospect is truly exciting. the human mandible. J Prosthet Dent 35:462-8, 1978. cannular guide for insertion of the anes- References 28. Wilson S, Johns P, Fuller PM, The inferior alveolar and 1. Robinson V, Victory Over Pain. Henry Schuman Publishing, mylohyoid nerves: an anatomic study and relationship to local thetic injection needle into the cancellous New York, 1946. anesthesia of the anterior mandibular teeth. J Am Dent Assoc bone. The Intraflow System (IntraVan- 2. Fink BR, Leaves and needles: the introduction of surgical 108:350-2, 1984. tage) is based upon a special low-speed local anesthesia. 63:77-83, 1985. 29. Chapnick L, Nerve supply to the mandibular dentition: a 3. Fink BR, History of neural blockade. In, Cousins MJ, review. J Can Dent Assoc 46:446-8, 1980. handpiece with a clutch and foot-pedal Bridenbaugh PO, eds, Neural Blockade in Clinical Anesthesia 30. Blanton PC, Roda RS, The anatomy of local anesthesia. J control system that permits perforation and Management of Pain, 2nd ed. JB Lippincott Co, Cal Dent Assoc 23(4):55-69, 1995. and injection with the handpiece in place, Philadelphia, 1988. 31. Gibson RS, Allen K, et al, The Wand vs. traditional injection: 4. Jastak JT, Yagiela JA, Donaldson D, Local Anesthesia of the a comparison of pain related behaviors. Pediatric Dent thus removing the need to switch from Oral Cavity. WB Saunders Co, Philadelphia, 1995. 22(6):458-62, 2000. handpiece to syringe. The Intraflow hand- 5. Hadda SE, Procaine: Alfred Einhorn’s ideal substitute for 32. Saloum FS, Baumgartner JC, et al, A clinical comparison piece system is about $900; the cost of cocaine. J Am Dent Assoc 64:841-5, 1962. of pain perception to the Wand and a traditional syringe. Oral 6. Dobbs EC, A chronological history of local anesthesia in Surg Oral Med Oral Pathol 89(6):691-5, 2000. disposable supplies is similar for all three dentistry. J Oral Ther Pharmacol 1:546-9, 1965. 33. Goodell GG, Gallagher FJ, Nicoll BK, Comparison of a systems, ranging from $1.50 to $2. 7. Malamed SF, Handbook of Local Anesthesia, 3rd ed. Mosby- controlled injection pressure system with a conventional Because intraosseous injections are into Year Book, St Louis, 1990. technique. Oral Surg Oral Med Oral Pathol 90(1):88-94, 2000. 8. Little JW, Falace DA, et al, Dental Management of the 34. Blanton PL, Jeske AH, Misconceptions involving dental the highly vascular cancellous bone tissue Medically Compromised Patient, 5th ed. Mosby-Year Book, St local anesthesia part 1: anatomy. Texas Dent J 4:296-306, 2002. space, use of vasoconstrictor-containing Louis, 1997. 35. Heine RD, Caughman WF, et al, Alternative methods for anesthetic agents is generally not advised 9. Goulet J-P, Perusse R, Turcotte J-Y, Contraindications inferior alveolar anesthesia. Compend Contin Educ Dent to vasoconstrictors in dentistry: Part III, pharmacologic 6(6):441-8, 1985. due to the rapid uptake of the agent into interactions. Oral Surg Oral Med Oral Path 74:692-7, 1992. 36. Loizeaux AD, Devos BJ, Inferior alveolar nerve anomaly. J the circulatory system with a subsequent 10. Yagiela JA, Adverse drug interactions in dental practice: Hawaii Dent Assoc 12:10-11, 1981. increase in patient heart rate.49,50, 62-64 interactions associated with vasoconstrictors. J Am Dent 37. Jablonski NG, Cheng CM, et al, Unusual origins of the Assoc 130:701-9, 1999. buccal and mylohyoid nerves. Oral Surg Oral Med Oral Pathol In a number of studies, from 2 percent to 11. Verbal communications, S. Merrick, anesthetic product 60:485-8, 1985. 15 percent of patients reported moderate manager, Septodont, Inc, 2002 and 2003. 38. Casey DM, Accessory mandibular canals. NY State Dent J to severe pain during perforation, needle 12. Haas DA, Lennon D, A 21-year retrospective study 44:232-3, 1978. of reports of paresthesia following local anesthetic 39. Wilson SS, Johns PI, Fuller PM, Accessory innervation of insertion, or injection of the anesthetic administration. J Can Dent Assoc 61:319-30, 1995. mandibular anterior teeth in cats: a horseradish peroxidase solution; and equal numbers of patients 13. Miller PA, Haas DA, Incidence of local anesthetic-induced study. Brain Res 298:392-6, 1984. reported postoperative pain, swelling, or neuropathies in Ontario from 1994-1998. J Dent Res 79(special 40. Barker BC, Davies PL, The applied anatomy of the iss):627(abstract), 2000. pterygomandibular space. Br J Oral Surg 10:43-55, 1972. bruising at the injection site.54 14. Haas DA, Localized complications from local anesthesia. J 41. McKissock MD, Meyer RD, Accessory innervation of the A variety of electronic anesthesia sys- Cal Dent Assoc 26(9):677-82, 1998. mandible: identification and anesthesia options. Genl Dent tems have come and gone from the dental 15. Fink BR, Kish SJ, Reversible inhibition of rapid axonal 6:662-71, 2000. transport in vivo by lidocaine hydrochloride. Anesthesiol 42. Donkor R, Wong J, Punnia-Moorthy A, An evaluation of the marketplace. Although these systems had 44:139-46, 1976. closed mouth mandibular block technique. Int J Oral Maxillofac their clinical successes, most practitioners 16. Rigler MI, Drasner K, et al, Cauda equina syndrome after Surg 19(4):216-9, 1990. found them frustrating to use in routine continuous spinal anesthesia. Anesth Analg 72:275-81, 1991. 43. Gow-Gates GAE, Mandibular conduction anesthesia: a new 17. Lambert DH, Hurley RJ, Cauda equina syndrome and technique using extraoral landmarks. Oral Surg 36:321-8, 1973. practice. The increased time for patient continuous spinal anesthesia. Anesth Analg 72:817-9, 1991. 44. Akinosi JO, A new approach to the mandibular nerve block. education about use of the system and the 18. Kane RE, Neurologic deficits following epidural or spinal Br J Oral Surg 15:83-7, 1977. large variance in predictable anesthesia anesthesia. Anesth Analg 60:150-61, 1981. 45. Gow-Gates GAE, Watson JE, Gow-Gates mandibular block: 19. Cowan A, Clinical assessment of a new local anesthetic applied anatomy and histology. Anesth Prog 36(4-5):193-5, from one patient to the next, and even be- agent: articaine. Oral Surg Oral Med Oral Pathol 43(2):174-80, 1989. tween different sites on the same patient, 1977. 46. Berezowski BM, Lownie JF, Cleaton-Jones PE, A have ultimately led to their discontinued 20. Donaldson D, James-Perdok L, et al, A comparison of comparison of two methods of inferior alveolar nerve block. J Ultracaine, DS (articaine Hcl) and Citanest, Forte (prilocaine Dent 16(2):96-8, 1988. use. In general, the systems were only use- Hcl) in maxillary infiltration and mandibular nerve block. J Can 47. Malamed SF, The Gow-Gates mandibular block: evaluation ful for relatively non-invasive procedures Dent Assoc 1:38-42, 1987. after 4,275 cases. Oral Surg 51:463-7, 1981. on a small percentage of patients. 21. Vahatalo K, Antila H, Lehtinen R, Articaine and lidocaine for 48. Replogle K, Reader A, et al, Anesthetic efficacy of the maxillary infiltration anesthesia. Anes Prog 40:114-6, 1993. intraosseous injection of 2 percent lidocaine (1:100,000

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epinephrine) and 3 percent mepivacaine in mandiular first molars. Oral Surg Oral Med Oral Pathol Radiol Endod 83:30-7, 1997. 49. Coggins R, Reader A, et al, Anesthetic efficacy of the intraosseous injection in maxillary and mandibular teeth. Oral Surg Oral Med Oral Pathol Radiol Endod 81:634-41, 1996. 50. Leonard MS, The efficacy of an intraosseous injection system of delivering local anesthetic. J Am Dent Assoc 126:81- 6, 1995. 51. D’Souza JE, Walton RE, Peterson LC, Periodontal ligament injection: an evaluation of the extent of anesthesia and postinjection discomfort. J Am Dent Assoc 114:341-4, 1987. 52. Malamed SF, The periodontal ligament (PDL) injection: an alternative to inferior alveolar nerve block. Oral Surg Oral Med Oral Pathol 53(2):117-121, 1982. 53. Walton RE, Abbott BJ, Periodontal ligament injection: a clinical evaluation. J Am Dent Assoc 103:571-5, 1981. 54. Brown R, Intraosseous anaesthesia: a review. Oral Health 3:7-14, 2000. 55. Hochman M, Chiarello D, et al, Computerized local anesthetic delivery vs. traditional syringe technique. New York State Dent J Aug/Sept:24-9, 1997. 56. Krochak M, Friedman N, Using a precision-metered injection system to minimize dental injection anxiety. Compendium 19(2):137-50, 1998. 57. Gibson RS, Allen K, et al, The Wand vs. traditional injection: a comparison of pain related behaviors. Pediatric Dent 22(6):458-62, 2000. 58. Friedman MJ, Hochman MN, A 21st century computerized injection system for local pain control. Compendium 18(10):995-1004, 1997. 59. Friedman MJ, Hochman MN, The AMSA injection: a new concept for local anesthesia of maxillary teeth using a computer-controlled injection system. Quintessence Int 29:297-303, 1998. 60. Spaeth D, Presto! Wand faces new competition. Dent Pract Report 4:55-6, 2001. 61. Levato CM, In pursuit of the pain-free injection. Dent Pract Report 4:34-36, 2002. 62. Dunbar D, Reader A, et al, Anaesthetic efficacy of the intraosseous injection after an inferior alveolar nerve block. J Endodon 22:481-6, 1996. 63. Nusstein J, Reader A, et al, Anaesthetic efficacy of the supplemental intraosseous injection of 2% lidocaine with 1:100,000 epinephrine in irreversible pulpitis. J Endodon 24:487-91, 1998. 64. Parents SA, Anderson RW, et al, Anaesthetic efficacy of the supplemental intraosseous injection for teeth with irreversible pulpitis. J Endodon 24:826- 8, 1998. To request a printed copy of this article, please contact/Alan W. Budenz, MS, DDS, MBA, UOP School of Dentistry, 2155 Webster St., San Francisco, CA 94115-2333.

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Nitrous Oxide-Oxygen: A New Look at a Very Old Technique

Stanley F. Malamed, DDS, and and Morris S. Clark, DDS

abstract Inhalation sedation utilizing nitrous oxide-oxygen has been a primary technique in the management of dental fears and anxieties for more than 150 years and remains so today. Though other, more potent, anesthetics have been introduced, nitrous oxide is still the most used gaseous anesthetic in the world. Administered properly with well- maintained equipment, the nitrous oxide-oxygen technique has an extremely high success rate coupled with a very low rate of adverse effects and complications.

authors iscovered in 1772, nitrous the discoverer of anesthesia -- committed

Stanley F. Malamed, oxide was, for almost 70 years, suicide while in jail on May 30, 1848, while DDS, is a professor in and a recreational drug. It was under the influence of the anesthetic gas chair of the Section of not until Dec. 10, 1844, in , to which he had become ad- Anesthesia and Medicine Hartford, Conn., at a travel- dicted. at the University of D ing “popular science” exhibition that the Though other, more potent, anesthet- Southern California School of Dentistry. potential of nitrous oxide to relieve pain ics have been introduced, nitrous oxide was appreciated. On that night, “Profes- remains the most used gaseous anesthetic Morris S. Clark, DDS, sor” Colton demonstrated nitrous oxide. in the world. It is commonly administered is a professor at the Attending the performance was a local as a part of every general anesthetic tech- University of Colorado dentist, . Wells noted that nique for the purpose of enabling a lesser Health Sciences Center School of Dentistry one of the men who had volunteered to amount of a more potent (and usually inhale nitrous oxide had seriously injured more toxic) general anesthetic agent to be his leg but was apparently unaware of employed. any pain. The next day, a reluctant Colton Surveys by the American Dental As- served as the anesthesiologist as an- sociation demonstrate that the percentage other dentist, Dr. John Riggs, extracted of American dentists employing nitrous a wisdom tooth from Dr. Wells’ mouth. oxide-oxygen (the procedure changed to After recovering from the effects of the include oxygen in the 1860s) is about 35 nitrous oxide, Wells stated that he had percent.4 been totally unaware of the procedure Interestingly, nitrous oxide-oxygen and that there had been no pain associ- has found an important niche in the area ated with it.1 of emergency medicine.5 Under the pro- Wells -- recognized by both the Ameri- prietary names Entonox and Dolonox, ni- can Dental Association in 18642 and the trous oxide-oxygen (in a 40 percent to 60 American Medical Association in 18703 as percent ratio), is employed by paramedical

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personnel in the prehospital management of pain associated with acute myocardial infarction.6 In some areas of the world, it is used in emergency medicine in lieu of opioid analgesics for the management of painful injuries.

Technique The technique for administration of nitrous oxide-oxygen inhalation sedation has changed little during the past several decades. One of the most important safety features associated with the tech- nique is the ability of the dentist or dental hygienista to administer to a patient the precise amount of nitrous oxide required to provide the desired level of central nervous system depression (sedation). This ability is termed “titration,” and it represents the most important safety Figure 1. Normal distribution curve for nitrous oxide-oxygen inhalation sedation. feature of this technique. When titrated properly (Table 1) the success rate of nitrous oxide-oxygen inhalation sedation School of Dentistry demonstrates that nitrous oxide-oxygen, which eventually is extremely high. Unpleasant side effects the typical inhalation sedation patient leads to his or her calming down, at which -- such as nausea, vomiting, and bizarre (middle of the bell-shaped curve) requires time the nasal hood is repositioned on behavioral responses -- do not occur when from 30 percent to 40 percent nitrous the nose and treatment commenced. This titration is performed. The administration oxide to achieve ideal sedation (Figure 1).7 procedure is repeated as often as needed. of a fixed concentration of nitrous oxide- It is important to note that there are oxygen (for example 50 percent to 50 patients at either end of this normal dis- The Equipment percent) routinely to all patients at each tribution curve who respond well to sig- Although the technique of nitrous visit simply makes no sense given the nificantly lower concentrations of nitrous oxide-oxygen delivery has changed little, ease with which titration may be carried oxide (hyperresponders -- left side of the during the past decades the inhalation out. The above-mentioned side effects are curve), while others require significantly sedation machine has undergone con- much more likely to be observed when higher levels of nitrous oxide to achieve siderable revision. Despite the introduc- titration is not employed. the same clinical effect (hyporesponders). tion of the ester-type local anesthetics The recommended technique of Titration enables the dentist to adequate- (e.g., procaine hydrochloride) into dental administration of nitrous oxide-oxygen ly sedate all of these patients. practice in 1904, nitrous oxide continued inhalation sedation for the cooperative In the precooperative pediatric patient to be administered as the sole agent in adult or child patient (a patient who will- (younger than 5) acceptance of the nasal general anesthesia. The administration ingly accepts the nasal hood) is presented hood is not likely. Indeed, with a scream- of 100 percent nitrous oxide produced in Table 1.7 ing or crying combative young patient, it what is called “anoxic anesthesia.” It Properly employing the technique is difficult to employ inhalation sedation wasn’t until the introduction in the late described described above will allow the successfully. In addition to the difficulty 1940s of the first amide local anesthetic overwhelming majority of apprehensive in placing the nasal hood in this situation, -- lidocaine hydrochloride -- that the need dental patients to be successfully sedated, the screaming/crying patient is primarily for nitrous oxide to provide pain control receiving their dental treatment in a much breathing through his or her mouth. In disappeared. Langa demonstrated that more comfortable and stress-free envi- the hands of a trained pediatric dentist, nitrous oxide in combination with oxygen ronment. Review of patient records from an acceptable technique is placement of would provide excellent “relative anal- more than 29 years of administration of the nasal hood over the mouth of the gesia,” which in combination with local nitrous oxide-oxygen inhalation sedation screaming/crying patient. In this man- anesthesia provided the dental patient at the University of Southern California ner, the patient receives large amounts of with pain-free treatment 8 The ability of

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the inhalation sedation unit to deliver 100 of all operational parameters by the device standard today. The digital accuracy and percent nitrous oxide became a potential frees the practitioner to concentrate on exacting control is highly recommended liability. The American Dental Associa- the patient’s needs. The device alerts the for patient comfort and safety. tion’s Council on Dental Materials, Instru- practitioner or staff to unusual param- ments, and Equipment adopted an Ac- eters requiring attention, similar to those Current Concerns About Nitrous Oxide ceptance Program for inhalation sedation seen in larger hospital-based systems. Several concerns have been addressed units that permitted the doctor to better The digital units deliver pure oxygen regarding the safety of inhalation seda- evaluate those units being considered for during the “flush” function by electroni- tion with nitrous oxide-oxygen inhala- purchase.9 The primary emphasis of this cally shutting off the nitrous oxide flow, tion sedation. These include the problem program has been the addition of safety as opposed to the flow tube units, which of abuse of nitrous oxide by health care features to these units aimed at making it only dilute the nitrous oxide delivered. professionals, sexual awareness related to difficult, if not impossible, to administer Again, the removal of extra steps in shut- nitrous oxide, and potential biohazards of less than 20 percent oxygen to the patient. ting down the nitrous oxide supply before chronic exposure to trace anesthetic gas. To receive a satisfactory classification, the pressing the “flush” button is removed Abuse of nitrous oxide by health manufacturer had to submit its devices to and greatly simplifies the practitioner’s care professionals: Nitrous oxide causes the Council on Dental Materials, Instru- tasks. euphoria and, therefore, as Sir Humphrey ments, and Equipment for evaluation. The The units contain flashing LEDs to Davy discovered in 1798, has a potential council publishes a listing of acceptable afford the practitioner a simple method of for abuse.12,13 This abuse is usually not as devices in the Journal of the American ensuring that the individual component addictive as some drugs, but nonetheless Dental Association, in the ADA Guide to gas is flowing and that the relative ratio can be a steppingstone to other drugs and Dental Therapeutics,10 and on the ADA and amount of flow is correct. Addition- can cause incapacitation of the affected Web site, www.ada.org. ally, the digital unit provides the capabil- person. Nitrous oxide should be given The many safety features incorporated ity of displaying the flow rate of either of the same respect given to all drugs.14,15 into the modern inhalation sedation unit the constituent gasses. The nonsilence- When chronically abused, nitrous oxide are listed in Table 2. able alarm function for oxygen depletion can have serious health consequences.16 Another significant, and more recent, ensures patient safety. The air intake valve The typical abuser of nitrous oxide change relates to the technology used to located on the bag tee provides room is usually older and probably from the control the precise flow of gasses deliv- air to the patient whenever the patient’s middle to upper class. If he or she has an ered through the inhalation sedation unit. breathing demand is greater than the inhalation sedation unit available, it has Although the old flow tube flowmeter combined output of the mixer head’s set- probably been altered in an attempt to technology is still available, it is being tings and reservoir bag volume. deliver a higher concentration of gas. A replaced by the state-of-the-art digital Various models of the electronic gas dentist living in Colorado placed a blanket electronic flow control devices, such as the mixing head allow mounting as a wall over his head to increase the concentra- Centurion Mixer and Digital MDM (Fig- unit, portable unit, countertop unit, or as tion even more. He became asphyxiated ure 2). Both of these devices are percent- a flush-mount unit in modern cabinetry. and could not be revived. Chronic inhala- age devices and overcome the limitations Digital heads have the most flexibility, tion (abuse) of nitrous oxide may lead to of the older flow tube technology. The especially when combined with various various neuropathies. This is particularly devices have resolution of the gas flow in remote bag tee options provided by the concerning if the loss of tactile sensation increments of 0.1 liter per minute, and manufacturer. The units are fully com- is associated with interference with their the total flow and percent of oxygen are patible with central gas supply systems occupation, i.e., dentist. The neuropathy is displayed digitally, eliminating the guess- such as the popular Flo-Safe Manifold, generally reversible but can be permanent. work or calculations required with simple Centurion Gas Manifold, and all existing Nitrous oxide is used for mood altera- flow tube devices. The ability to clean the scavenging systems. It is available with tion, sedation, and analgesia. It is the front panel with just a wipe reduces the the American Dental Association recom- weakest of all general anesthetic agents. potential of cross patient infection, an is- mended 45 liter per minute scavenging In the right circumstances, it has the sue associated with the crevices created by control valve in various mounting con- potential to cause unconsciousness. knobs and levers. Patient safety is ensured figurations. 11 Sexual awareness related to nitrous with built-in alarms for all gas depletion Electronic digital administration heads oxide: There have been reports of sexual conditions along with servo control of for delivery of conscious sedation advance abuse of patients while under the influ- the gas delivery (what you see is what you the art of dentistry. The digital heads once ence of a variety of anesthetics.17-19 As get). Continuous internal self-monitoring considered the wave of the future are the expected, nitrous oxide has also been

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associated with scattered reports of im- siologists in which it was demonstrated Occupational Safety and Health became propriety between male practitioners and that they suffered a higher incidence of interested in these studies and established female patients. Nitrous oxide does cause irritability, headache, fatigue, nausea, 50 ppm as the maximum exposure limit euphoria and, in high concentrations, pruritus, spontaneous abortion, and fetal for personnel in the dental setting. It was dreaming hallucinations and, as described malformation than non-operating room determined that 25 ppm was achievable in by Sir Humphrey Davy in 1798, “volup- personnel. It must be emphasized that the operating room, and therefore this be- tuous sensations.” The cases of record in these studies nitrous oxide was but came the standard for that setting. Mul- always involve three elements that place one of many gases under investigation. tiple attempts to reproduce the research the practitioner at risk: treating a patient Because it is the most commonly used results of Bruce, Bach, and Arbit have without an assistant in the operatory, inhalation anesthetic, nitrous oxide will failed;25 interestingly, these researchers high concentrations of nitrous oxide, and be found in all samples of air taken from have retracted their conclusions, indicat- failure to titrate the patient to avoid the operating rooms. It is used in conjunc- ing the results were not based on biologic extension beyond their range of therapeu- tion with oxygen and other more potent factors.26 tic sedation. inhalation anesthetics such as , The results of this “research,” as one Nitrous oxide requires hosing that can desflurane, and . Therefore, would expect, caused a concern and drape around the shoulders for reten- it has been impossible to separate the subsequent decline in the use of nitrous tion of the mask. It is important to allow effects of any one of these gases from the oxide. Indeed, there was alarm in the the patient to adjust the mask on his or others. Because of the special nature of manufacturing and equipment industry her face and to help the patient under- dental practice, in which virtually the only for nitrous oxide that bordered on a crisis. stand that it is connected to the hosing. inhalation anesthetic employed is nitrous In 1995, a worldwide literature search The hosing on a euphoric patient can oxide, the findings of these operating on the topic of biohazards associated be misconstrued to be an inappropriate room studies were not applicable to the with nitrous oxide use was conducted by contact. Also, the patient should be al- dental profession. Clark.27 Eight hundred and fifty cita- lowed to fully recover. It may take longer In the United States, Cohen and col- tions were retrieved, of which 23 met the than three to five minutes. Jastak and leagues22,23 published articles dealing predetermined criteria for scientific merit. Malamed have reported a series of cases with anesthetic health hazards in the den- The conclusion drawn from this literature involving nitrous oxide and sexual phe- tal setting. One article contained a study review indicated that there was no scien- nomena.17 Malamed reports in an unpub- that surveyed more than 50,000 dentists tific basis for the previously established lished survey that a percentage of dental and dental assistants who were exposed threshold levels for the hospital operating hygiene students reported increased to trace anesthetics. The results suggested room or the dental setting. This research feelings of sexuality and/or arousal while that long-time exposure to anesthetic became the impetus for a meeting of under the effects of nitrous oxide.20 They gases could be associated with an increase interested parties representing dentistry, also reported some instances of orgasm. in general health problems and problems government, and manufacturing. A result Nitrous oxide should be employed with with the reproductive system in particu- of the September 1995 meeting, spon- confidence. Employing simple guidelines lar. While this study was retrospective in sored by the American Dental Associa- will ensure there are no difficulties with nature, it only fueled the concern regard- tion’s Council of Scientific Affairs and any sexual issues and the administrator of ing the safety of nitrous oxide in the Council of Dental Practice, was the formal nitrous oxide. dental office. Unfortunately, this “study” position statement that a maximum Potential biohazards of chronic expo- did not contain any measured data of nitrous oxide exposure limit in parts per sure to trace anesthetic gas: Nitrous oxide these trace gases that were involved in any million has not been determined.28 is found naturally in the atmosphere in of the environs reported. The specific biologic issue is the minute quantities. It is quickly reversible In 1974, Bruce, Bach, and Arbit24 inactivation of methionine synthetase. in action, but is it totally harmless? investigated the possibility of nitrous This enzyme is linked to vitamin B-12 Little was known about the possible oxide affecting perceptual cognition and metabolism. Vitamin B-12 is necessary for effects of inhalation of minute amounts psychomotor skills of personnel exposed DNA production and subsequent cellular of anesthetic vapors until the late 1960s. to varying concentrations of the gas. They reproduction. Nitrous oxide does affect Until this time, little was done to elimi- reported that just hours of exposure to methionine synthetase and does, in high nate anesthetic vapors being delivered as little as 50 ppm could result in au- concentration and with long exposure into the ambient air from the anesthesia diovisual impairment. Despite multiple (longer than 24 hours), have an effect on machines. In 1967, Vaisman21 published attempts to duplicate their results, all reproduction.29 However, to date there is the results of a survey of Russian anesthe- efforts failed. The National Institute of no evidence that a direct causal relation-

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situation to make the interaction with the Table 1. Inhalation Sedation patient as brief and concise as possible. Technique7 The use of a rubber dam is highly effective 1. A 5 or 6 Lpm (liter per flow minute) of 100 at decreasing trace nitrous oxide exposure. percent oxygen is established, and the nasal Monitoring of trace nitrous oxide: hood is placed on the patient’s nose. The The most accurate and effective method patient is instructed to adjust the mask as of determining nitrous oxide levels in needed for comfort. ambient air is through an infrared nitrous 2. If necessary, the flow rate is adjusted (more, oxide analyzer.33 The infrared analyzer less, the same) while the patient is breathing can detect gases from the previously men- 100 percent oxygen. The patient must be able Figure 2. Digital electronic flow control device, tioned 1 ppm to an upper limit of 2,000 to breathe comfortably, in and out, through his Digital MDM. Photograph courtesy of Matrx or her nose with the nosepiece in position. (Orchard Park, N.Y.). ppm. These devices are very expensive but can be rented from a gas service company. 3. A flow of nitrous oxide is started, at approxi- A gas supplier will have the resources mately 20 percent initially. Nitrous oxide is then added in ~10 percent increments every 60 sec- ship exists between reproductive health available for dentists to rent an infrared onds until an ideal sedation level* is reached. and scavenged low levels of nitrous ox- spectrophotometer for nitrous oxide ide.30,31 Sweeney and colleagues32 were analysis. 4. When the patient states that he or she feels pleasant and more relaxed, the ideal level of the first to link reproductive problems In 1997, the American Dental Asso- clinical sedation* has been achieved. in humans with chronic nitrous oxide ciation published recommendations for exposure. He used a sensitive test -- the responsible maintenance and monitoring 5. Once the ideal level of sedation* is achieved, local anesthetic is administered and the deoxyuridine suppression test -- to ac- of nitrous oxide and its equipment. They planned dental/surgical procedure completed. curately determine the first signs of this are listed in Table 3.28 biologic effect in humans. Sweeney found 6. Nitrous oxide flow is terminated, and the patient is permitted to breathe 100 percent that chronic exposure levels of 1,800 ppm Summary oxygen at a flow rate equivalent to the estab- of nitrous oxide did not exert any detect- Inhalation sedation utilizing nitrous lished Lpm for the patient. This may be started able biologic effect in humans. Sweeney oxide-oxygen has been a primary tech- earlier than at the absolute completion of the suggests that 400 ppm is a reasonable nique in the management of dental fears procedure to ensure a more expedient recov- exposure level that is both attainable and and anxieties for more than 150 years and ery. Oxygen is given for minimally three to five minutes, longer if clinical signs of sedation significantly below the biologic threshold. remains so today. persist. Today, it is below the standard of care Administered properly with well- not to have a scavenging nasal hood.27 maintained equipment, the technique has 7. The patient may be dismissed from the den- tal office unescorted if it is the doctor’s belief The scavenging nasal hood is a double an extremely high success rate coupled that he or she is completely recovered from mask: an inner mask contained within a with a very low rate of adverse effects and sedation. slightly larger outer mask. The inner mask complications. * Ideal sedation has been achieved when the receives a fresh supply of nitrous oxide- patient states that he or she is experiencing oxygen from the inhalation sedation unit Notes some or all of the following: feeling of warmth and delivers gas to the nose of the patient a. The administration of nitrous oxide- throughout his or her body, numbness of the through tubes that are slightly larger in oxygen inhalation sedation by trained hands and feet, numbness of the soft tissues of the oral cavity, a feeling of euphoria, and a feel- diameter than the other tubes. The outer, dental hygienists is permitted by some ing of lightness or of heaviness of the extremi- slightly larger, mask connects to slightly state dental boards ties. Note that not all patients will experience smaller tubes that connect with the the same symptoms. vacuum system. On exhalation through the nose all exhaled gases are vented into the outer nasal hood and then, via the vacuum, are carried away from the patient and the treatment area. Two of the most common causes of nitrous contamination in the office are from patients’ talking and mouth breathing. The clinician should recognize this problem and attempt to modify the

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Table 2. Safety Features Incorporated placed on the patient. A good, comfortable fit abuse of nitrous oxide. Neurology 28:504, 1978. 17. Jastak JT, Malamed SF, Nitrous oxide and sexual Into Modern Inhalation Sedation should be ensured. The reservoir (breathing) bag should not be over- or underinflated while phenomena. J Am Dent Assoc 101:38, 1980. Units the patient is breathing oxygen (before the 18. Lambert C, Sexual phenomena, , and nitrous oxide sedation. J Am Dent Assoc 105:990, 1982. administration of nitrous oxide). Alarm 19. Gillman MA, Assessment of the effects of analgesic Color coding 8. The patient should be encouraged to mini- concentrations of nitrous oxide on human sexual response. Int Diameter index safety system mize talking and mouth breathing while the J Neurosci 43(1-2):27, 1988. 20. Malamed SF, Serxner K, Wiedenfeld AM, The incidence Emergency air inlet mask is in place. Lock of sexual phenomena in females receiving nitrous oxide and oxygen inhalation sedation. J Am Analg Soc 22(2):9, 1988 Minimum oxygen liter flow 9. During administration, the reservoir bag should be periodically inspected for changes in 21. Vaisman A, Work in surgical theatres and its influence on Minimum oxygen percentage the health of anesthesiologists. Eksp Khir Anestheziol 3:44, Oxygen fail-safe tidal volume; and the vacuum flow rate should 1967. Oxygen flush button be verified. 22. Cohen EN, Brown BW Jr, et al, A survey of anesthetic health Pin index safety system hazards among dentists. J Am Dent Assoc 90:1291, 1975. 10. On completing administration, 100 percent Quick-connect for positive-pressure oxygen 23. Cohen EN, Brown BW Jr, et al, Occupational disease in oxygen should be delivered to the patient for Reservoir bag dentistry and chronic exposure to trace anesthetic gases. J Am five minutes before the mask is removed. In Dent Assoc 101:21, 1980. this way, both the patient and the system will 24. Bruce DL, Bach MJ, Arbit J, Trace anesthetic effects Table 3. ADA Recommendations be purged of residual nitrous oxide. An oxygen on perceptual, cognitive, and motor skills. Anesthesiology for Maintenance and Monitoring flush should not be used. 40:453-8, 1974. 25. Cohen EN, Belville JW, Brown BW, Anesthesia, pregnancy of Nitrous Oxide-Oxygen and 11. Periodic (semiannual interval is suggested) and miscarriage: a study of operating room nurses and Equipment28 personal sampling of dental personnel, with anesthetists. Anesthesiology 35:343, 1971. emphasis on chairside personnel exposed to 26. Yagiela JA, Health hazards and nitrous oxide: a time for 1. The dental office should have a properly nitrous oxide, should be conducted (for exam- reappraisal. Anesth Prog 38:1-11, 1991. installed nitrous oxide delivery system. This ple, through use of diffusive sampler [dosim- 27. Clark M, Brunick A, Handbook of Nitrous Oxide and Oxygen includes appropriate scavenging equipment eter] or infrared spectrophotometer). Sedation. Mosby, St Louis, 1999. with a readily visible and accurate flow meter 28. ADA Council on Scientific Affairs, ADA Council on Dental (or equivalent measuring device), a vacuum Practice, Nitrous oxide in the dental office. J Am Dent Assoc pump with the capacity for up to 45 liters of References 128:364-5, 1997. 29. Fujinagra M, Baden JM, Mazze RI, Susceptible period air per minute per workstation, and a variety 1. Raper HR, Man Against Pain. Prentice-Hall, New York, 1945. of nitrous oxide teratogenicity in Sprague-Dawley rats. of sizes of masks to ensure proper fit for indi- 2. American Dental Association, Transactions of the fourth annual meeting at Niagara Falls, NY, 1864. Teratology 40:439-44, 1989. vidual patients. 3. Archer WH, Life and letters of Horace Wells, discoverer of 30. Rowland AS et al, Reduced fertility among women employed as dental assistants exposed to high levels of 2. The vacuum exhaust and ventilation exhaust anesthesia. J Am Coll Dent 11:81, 1944. nitrous oxide. New Eng J Med 327:993-7, 1992. should be vented to the outside (for example, 4. Jones TW, Greenfield W, Position paper of the ADA ad hoc committee on trace anesthetics as a potential health hazard in 31. Eger E II, Fetal injury and abortion associated with through the vacuum system) and not in close dentistry. J Am Dent Assoc 95:751, 1977. occupational exposure to inhaled anesthetics. J Am Assoc proximity to fresh-air intake vents. 5. Thompson PL, Lown B, Nitrous oxide as an analgesic in acute Nurse Anesth 59:309-12, 1991. 32. Sweeney B, Bingham RM, et al, Toxicity of bone marrow in 3. The general ventilation should provide good myocardial infarction. J Am Med Assoc 235:924, 1976. 6. O’Leary U, Puglia C, et al, Nitrous oxide anesthesia in dentists exposed to nitrous oxide. Br Med J 291:567, 1985. room air mixing. patients with ischemic chest discomfort: effect on beta- 33. Lane GA, Measurement of anesthetic pollution in oral surgery offices. J Oral Surg 36:444, 1978. 4. Each time the nitrous oxide machine is first endorphins. J Clin Pharmacol 27(12):957, 1987. To request a printed copy of this article, please contact/ turned on and every time a is 7. Malamed SF, Sedation: A Guide to Patient Management, 4th ed. CV Mosby, St Louis, 2003 Stanley F. Malamed, DDS, 23765 Harwich Place, West Hills, CA changed, the pressure connections should be 8. Langa H, Relative Analgesia in Dental Practice, 2nd ed. 91307-1811. tested for leaks. High-pressure line connec- Saunders, Philadelphia, 1976. tions should be tested for leaks quarterly. A 9. ADA Council on Dental Materials, Instruments, and soap solution may be used to test for leaks. Equipment, Revised guidelines for the acceptance program Alternatively, a portable infrared spectropho- for nitrous oxide-oxygen sedation machines and devices. tometer can be use to diagnose an insidious American Dental Association, Chicago, 1986. leak. 10. ADA Council on Dental Materials, Instruments, and Equipment, ADA Guide To Dental Therapeutics, 2nd ed. 5. Prior to first daily use, all nitrous oxide equip- American Dental Association, Chicago, 2002. ment (reservoir bag, tubings, mask, connectors) 11. ADA Council of Scientific Affairs, ADA Council on Scientific should be inspected for worn parts, cracks, Practice, Nitrous oxide in the dental office. J Am Dent Assoc holes, or tears. They should be replaced as 128:364-5, 1997. necessary. 12. Gillman MA, Nitrous oxide abuse in perspective. Clin Neuropharmacol 15(4):297, 1992. 6. The mask may then be connected to the tub- 13. Malamed SF, Orr DL II, et al, The recreational abuse of ing and the vacuum pump turned on. All appro- nitrous oxide by health professionals. J Calif Dent Assoc 8:38, priate flow rates (that is, up to 45 L/min. or per 1980. 14. Gillman MA, Nitrous oxide: an opioid addictive agent. Am J manufacturer’s recommendations) should be Med 81:97, 1986. verified. 15. Aston R, Drug abuse: its relationship to dental practice. 7. A properly sized mask should be selected and Dent Clin North Am 28(3):595, 1984. 16. Layzer RB, Fishman RA, Schafer JA, Neuropathy following

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An Overview of Outpatient Sedation and General Anesthesia for Dental Care in California

Tim Silegy, DDS, and Roger S. Kingston, DDS

abstract This paper reviews the principal pharmacologic interventions for the management of pain and anxiety in the apprehensive dental patient, including oral sedation, intravenous sedation, and general anesthesia.

authors ccess to dental care is a highly In the 1960s, Southern California pio- debated issue at present, as neers such as Drs. Nils Jorgensen, Oran Tim Silegy, DDS, is a diplomate of the dentists, public health offi- K. Bullard, Adrian Hubbell, Howard Davis, American Board of cials, politicians, and patient Ed Boller, Lee Reeve, John Lytle, and Oral and Maxillofacial advocates examine the demo- Frank McCarthy introduced and refined Surgery. He maintains a Agraphics and distribution of dental care in intravenous sedation and general anes- private practice in Long California. thetic techniques for in-office dentistry. Beach, Calif. One of the barriers to dental care for a These pioneers had concern for patient Disclosure significant population subgroup, possibly as safety and advocated for safety standards Dr. Silegy gives basic, large as 30 percent, is fear and anxiety.1 At and governing legislation. advanced, and pediatric best, dental patients who experience fear, Currently, the dental anesthesia facul- life support lectures anxiety, and hypersensitivity to pain will ties of the California dental schools teach for CME Associates in Orange, Calif., and move in the dental chair and recall dental undergraduate dental students, graduate is the director of the visits negatively. Most significantly, many students, and postgraduate practicing den- oral and maxillofacial patients will avoid needed dental care, con- tists to provide dental care with sedation surgery assistant’s sequently suffering unnecessary morbidity. and general anesthesia. The University of course sponsored Perhaps dentistry’s greatest contribu- California at Los Angeles and Loma Linda by the California Association of Oral and tion to humankind has been the introduc- University offer two-year residency train- Maxillofacial Surgeons tion of anesthesia and anesthetic agents ing programs in dental anesthesiology. in Roseville, Calif. to dull or eliminate the physical and Dental anesthesiology, while not psychological effects of pain. Beginning in recognized as a by the American the 1840s with the popularization of ether Dental Association, is a field wherein by Dr. William T.G. Morton and nitrous trained and qualified dentists limit their oxide by Dr. Horace Wells, the interest of practice to teaching and providing anes- dentists in improving the dental experi- thesia services for dentistry. Professional ence is well-documented and voluminous. organizations such as the American Soci-

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ety of Dentist Anesthesiologists and the manage the potential complications as- General Anesthesia American Dental Society of Anesthesia sociated with deeper levels of anesthesia. General anesthesia is a controlled exist to promote excellence in dental anes- Therefore, the California Dental Practice state of depressed consciousness or thesia through education and research.2 Act defines three anesthetic levels and unconsciousness, accompanied by partial Equipped with portable monitors, regulates their administration .7 or complete loss of protective reflexes, many dentist anesthesiologists provide a produced by a pharmacologic or non- full range of anesthesia services, ranging Pediatric Oral Conscious Sedation pharmacologic method, or a combination from light sedation to general anesthesia, Pediatric oral conscious sedation is a thereof. for children, adults, and individuals with minimally depressed level of conscious- In California, all licensed dentists may special needs, in the offices of primary ness in a minor patient, produced by oral administer local anesthesia and nitrous care dentists. This represents a consider- medication, that retains the patient’s oxide-oxygen to adults and children. The able cost savings compared to treating ability to maintain independently and same dental license also allows oral seda- these same patients in outpatient surgical continuously an airway, and respond tives to be administered to patients 13 centers and hospitals. appropriately to physical stimulation and years of age and older. Dentists wishing verbal command. “Minor patient” means a to administer oral sedatives to children, California Law dental patient younger than 13. intravenous sedation, or general anesthe- The Dental Board of California has sia, require a special permit to do so. The implemented legislative regulations to Conscious Sedation requirements for these permits are listed establish minimum standards for train- Conscious sedation is a minimally in Table 1. ing, facilities, and monitoring for most depressed level of consciousness produced anesthetic techniques. Guidelines devel- by a pharmacologic or nonpharmacologic Indications oped by the Southern California Society of method, or a combination thereof, that Conscious sedation and general an- Oral and Maxillofacial Surgeons served as retains the patient’s ability to maintain esthesia in the dental office are generally a framework for this legislation. independently and continuously an air- limited to healthy (ASA Class I and Class Guedel was the first to describe anes- way and respond appropriately to physical II) patients. When interviewing the patient thetic levels.3 His observation of patients stimulation and verbal commands. Con- at the time of consultation, in addition to undergoing ether anesthesia provides a scious sedation does not include condi- reviewing a patient’s medical history and basis for our understanding today. The tions resulting from the administration performing a dental exam, it is important American Society of Anesthesiologists, of oral medications or the administration for the dentist to evaluate the patient’s the American Dental Association, the of a mixture of nitrous oxide and oxygen, level of anxiety. Patients with a history American Academy of Pediatric Den- whether administered alone or in com- of “bad” dental experiences in childhood, tists, and others have defined anesthetic bination with each other. The drugs and claustrophobia, low pain tolerance, or depth.4-6 Because airway protective techniques used in conscious sedation substance abuse are likely to benefit from reflexes are progressively depressed with shall have a margin of safety wide enough some type of pharmacosedation. increasing depth of anesthesia, more to render unintended loss of conscious- Sedation is defined as a state of drows- training and experience is needed to ness unlikely. iness or mental clouding. Frequently used

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synonyms include anxiolysis or relax- barbiturates, opioids, dissociatives, and In the case of intravenous sedation, its ation. The limbic system is responsible for others are commonly used alone or in long duration of action makes it a good awareness, and inhibition of this area of combination. These agents are summa- choice for longer procedures. Diazepam the brain results in a sense of tranquility rized in Table 2. is metabolized in the liver. An active by- and well-being. Hypnosis refers to central product of this metabolism is oxazepam, nervous system depression, principally of Benzodiazepines which contributes to a reduced yet pro- the reticular activating system, resem- Benzodiazepines act on gamma- longed sedative effect. Care must be taken bling normal sleep. Agents that produce amino-butyric-acid receptor complexes when using the drug on elderly patients, these effects are collectively referred to as in the central nervous system. When as they are typically much more sensitive sedative-hypnotics. As in normal sleep, activated, these receptors increase the to the sedative effect and tend to need a appropriately sedated patients may close passage of chloride ion through discrete longer period of recovery. their eyes and have dreams but can inde- channels, hyperpolarizing nerves in the is about 2.5 times as pendently maintain their airway and be limbic system, which results in a sense potent as diazepam and has greater easily awakened. of relaxation. Benzodiazepines have little amnestic properties. It is water-soluble analgesic effect and are frequently used in and is distributed as an aqueous solution Commonly Used Agents conjunction with opioids when used for for injection. It is also available premixed The principal inhalational anesthetic intravenous sedation. with cherry syrup for oral administra- agent in use today for sedation is nitrous Diazepam was first synthesized in the tion. Midazolam undergoes rapid redis- oxide.8 The use of nitrous oxide is exten- early 1960s and commonly referred to as tribution and has a significantly shorter sively reviewed elsewhere in this issue by “mother’s little helper.” At one time, it was half-life than diazepam, making it an ideal Dr. Stanley Malamed. While some have the most frequently prescribed medica- agent for short procedures. Additionally, advocated the use of halogenated hydro- tion in the United States.11 As is the case because it has no active metabolites, there carbons (desflurane and sevoflurane) to for all benzodiazepines, diazepam effec- is little “hangover” effect as is the case provide sedation, the need for anesthesia tively reduces anxiety and is a profound with diazepam. machines and vaporizers limits their use amnestic. Diazepam is available as a pill or Triazolam is a benzodiazepine de- principally to outpatient surgical facilities dissolved in propylene glycol for injection. signed principally to treat insomnia. It and hospital operating rooms.9-10 Propylene glycol can irritate smaller veins is distributed in pill form and has been A number of non-inhalational drugs and has been associated with phlebitis. found to be very effective when used for have sedative and, in higher doses, general Diazepam has a wide margin of safety and sedating anxious dental patients. Fol- anesthetic properties. Benzodiazepines, is effective both orally and intravenously. lowing oral administration, it has a peak

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effect at one hour and a half-life of two in the early 1960s. to three hours. Kaufman and colleagues Until last year, sodium methohexital found a 0.25 to 0.50 mg oral dose of tri- was the most commonly used general azolam taken one hour prior to treatment anesthetic agent in the oral and maxil- to be as efficacious as a mean dose of 19.3 lofacial surgery office. Its rapid onset and mg of diazepam titrated intravenously.12 relatively short duration of action make it Baughman and colleagues found 0.5 mg ideal for inducing general anesthesia for of oral triazolam to produce significant short procedures like third-molar removal. .13 Respiratory depression, laryngospasm, The administration of multiple doses hiccups, and resistance are common side of triazolam with early discharge after re- effects that are easily managed by experi- versal with sublingual flumazenil has been enced practitioners. Due to a manufactur- advocated by several continuing education ing shortage in 2002, many surgeons have seminars.14 To date, no controlled clinical switched to alternative agents such as studies have demonstrated this to be a and . safe technique. release, nausea, vomiting, and postural hypotension. As is also the case with Ketamine Opioids , meperidine should not be used Ketamine is a phencyclidine deriva- Opioids exert their effect on the cen- in patients taking monamine oxidase tive that produces profound analgesia and tral nervous system by interacting with inhibitors, as delirium and cardiovascular amnesia. Unlike other anesthetic agents, specific receptors in the brain and spinal collapse have been reported.15 it does not depress the reticular activat- cord blunting the response to excitatory Fentanyl citrate is perhaps the most ing system; rather, it blocks transmission neurotransmitters, namely acetylcholine commonly used opioid in anesthesia. It is of sensory impulses from the reticular and substance P (Table 3). Because the 100 times more potent then and activating system to the cerebral cortex opioid agonists are not specific for any has a duration of action much shorter than at the thalamus. Consequently, there is one receptor, the desirable effects of that of meperidine. Corresponding with little respiratory depression; and protec- euphoria, sedation, and analgesia are fre- increased potency is an increased incidence tive airway reflexes remain intact. It is quently accompanied by nausea, dyspho- of respiratory depression. Too rapid an available in liquid form for intravenous ria, and respiratory depression, especially administration of the drug can also result and intramuscular injection and has been in higher doses. Consequently, they are in a spasm of the diaphragm and skeletal administered orally. Many practitioners seldom used as a lone agent for sedation. muscles commonly referred to as “stiff- are concerned with reports of hallucina- Opioid agonist-antagonists like pen- chest syndrome.” 16 This occurs rarely in tions while emerging from the effects tazocine, nalbuphine, and butorphanol sedative doses and can be easily managed of the drug. This can be prevented with agonize some receptors but antagonize by administering a muscle relaxant. the simultaneous administration of a others. They were once popular because benzodiazepine.18 Ketamine has both of self-limiting respiratory-depressant Barbiturates sympathomimetic (increases heart rate effects but are seldom employed by anes- Barbiturates, like benzodiazepines, act and causes bronchodilation) and cholin- thesia providers today. on the gamma-amino-butyric-acid recep- ergic (causes hypersalivation and bron- Meperidine hydrochloride and fen- tor complex. They are available in pill form chial secretion) effects. Consequently, tanyl citrate are the most commonly used or as a powder reconstituted for injection. an anticholinergic such as atropine or opioids for intravenous sedation and gen- Prior to the synthesis of diazepam, they glycopyrolate is frequently administered eral anesthesia. When used in conjunc- were used frequently as minor tranquiliz- concomitantly. tion with benzodiazepines, they produce ers. Today, barbiturates are used mainly to a synergistic sedative result, effectively induce general anesthesia. Sodium pento- Propofol decreasing the overall dosage of drugs thal is commonly used in the hospital en- Propofol is a di-isopropyl-phenol un- needed to elicit the desired effect. vironment and was the first barbiturate to like any other anesthetic agent. It is highly About one-tenth as potent as mor- be used by oral and maxillofacial surgeons lipid-soluble, which accounts for its rapid phine sulfate, meperidine is a relatively for third-molar removal.17 Its tendency uptake and short duration of action. It is weak analgesic. When used intravenously to cause respiratory depression and long a potent amnestic and has been found to it has a duration of 30 to 60 minutes. duration of action have limited its use in be a powerful antiemetic.19 In low doses, Unwanted side effects include histamine the dental office, and it was superseded by it is an effective sedative. Due to its rapid

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redistribution, it is frequently adminis- cooperation from the patient. Ketamine An added benefit of using a benzodiaz- tered as a continuous infusion using an is an ideal intramuscular drug. With an epine-opioid combination for IV sedation infusion pump. onset of 10 minutes and minimal associ- is that in case of a medical emergency, ated respiratory depression, it renders pa- both benzodiazepines and opioids are Anesthetic Technique tients cataleptic, facilitating treatment or readily reversible. Flumazanil competi- the establishment of intravenous access. tively displaces benzodiazepines from Oral Sedation the gamma-amino-butyric-acid receptor Oral (enteral) sedation is ideal for Intravenous Sedation complex. Naloxone is the reversal agent slightly anxious patients requiring tra- Contrary to popular opinion, the for opioid analgesics. Care must be taken ditionally nonpainful dental procedures utilization of intravenous sedation does to observe the patient after the admin- such as cosmetic and restorative dentistry. not directly provide for a deeper level of istration of a reversal agent, as patients The principal advantages of oral seda- sedation than oral administration. The may become re-sedated if the half-life tion include ease of administration, as major advantage of IV sedation is that it of the anesthetic agent exceeds that of there is no need for intravenous access, allows the clinician to maintain precise the reversal agent. While propofol and and favorable patient acceptance. Oral control over the patient’s level of seda- ketamine have been used in low doses to benzodiazepines such as diazepam and tion through the administration of small provide sedation, it is the opinion of the triazolam are particularly effective. When incremental dosages of medication, a authors that they do not have a margin of used in recommended dosages, they are technique known as titration. By titrating safety wide enough to render unintended very safe and carry with them very few medications, a patient’s level of con- loss of consciousness unlikely, and hence direct contraindications. Midazolam is sciousness can be carefully adjusted and do not fall within the legislative guidelines also an effective oral sedative; however, its the level of sedation controlled. of “sedative” agents. use is chiefly reserved for premedication The procedure involves gaining in- in children. travenous access in the hand or forearm General Anesthesia A major disadvantage of oral sedation and maintaining it throughout the course General anesthesia is indicated for is the inability to tailor dosages for individ- of the procedure. Those individuals with management of highly anxious and fearful ual patients. When taken orally, anesthetic “needle phobia” benefit from the use of (phobic) patients requiring restorative agents are absorbed by the portal circula- topical anesthetics such as lidocaine prilo- dentistry and for oral surgery patients un- tion and pass through the liver, where caine cream or spray refrigerants such as dergoing procedures where local anesthesia they are metabolized prior to entering the ethyl chloride. Patients are typically given alone would not provide sufficient comfort. central circulation. This first pass effect supplemental oxygen via a nasal canula This form of anesthesia is the most uni- makes it difficult to predict the bioavailabil- or nasal hood in conjunction with nitrous formly dependable anesthesia modality. ity of the agent and, consequently, just the oxide. Their blood pressure and heart rate In the outpatient environment, a right dose. Drugs that are unstable in an are monitored periodically and oxygen general anesthetic begins in much the acidic environment make be deactivated by saturation is continuously monitored same way as IV sedation. Because a deeper gastric acid in the stomach. with pulse oximetry. A precordial stetho- plane of anesthesia is expected, sedative As is the case for patients who receive scope is commonly used to evaluate medications may be administered more parenterally administered anesthetic medi- heart rate and breath sounds during the rapidly; and commonly a third agent is cations, dental patients who have taken procedure. added to induce unconsciousness. This oral sedatives should be driven to and from Benzodiazepines are frequently used “balanced” anesthesia technique, provides their dental appointments by a respon- as initial agents. Small doses are admin- anxiolysis, analgesia, and amnesia in a sible adult and should not drive or operate istered until the patient’s eyelids droop predictable and safe manner. dangerous machinery until fully recovered (Verril’s sign) and his or her speech is Dr. Adrian Hubble popularized the use from the effects of the medication. slurred. An opioid may be added next to of sodium methohexital for induction of deepen the level of sedation and provide general anesthesia in patients undergoing Intramuscular Injection analgesia. While effective in reducing third-molar removal.20 The surge technique The intramuscular route of drug ad- anxiety and blunting the pain response, involves injecting an initial large bolus of ministration parallels oral administration. IV sedation alone does not eliminate the the agent followed by frequent smaller Agents undergo first-pass metabolism in need for local anesthesia. Consequently, boluses or “bumps.”21 This technique is still the liver, making the end effect difficult to care must be taken to ensure that the practiced by many oral surgeons today when predict. The major advantage of intra- patient is numb prior to starting and using sodium methohexital or propofol for muscular injection is that it requires little throughout the course of treatment. third-molar anesthesia.

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The use of a continuous small infusion for healthy patients. Conclusion of agent is another frequently used tech- Second, most practitioners surround Although access to dental care is still nique, being particularly useful for longer themselves with a highly trained team, an issue in California, no patient should surgical and restorative cases. Following thoroughly prepared and equipped to find it impossible to receive needed dental an initial large bolus, a slow intravenous manage anesthetic emergencies. All care because of fear and anxiety. Many drip, or an infusion pump, administers a personnel involved in patient care are levels of anesthetic intervention can be continuous predetermined amount of an required by law to have current training provided by appropriately trained den- agent or agents, allowing the practitioner in basic life support. Practitioners holding tists. Available techniques include local to maintain tight control on the level of general anesthesia permits are required anesthesia, nitrous oxide/oxygen analge- anesthesia. Propofol and propofol/opioid to be current in advanced cardiac life sia, oral sedation, intravenous conscious and propofol/ketamine combinations support. Advanced training programs in sedation, and general anesthesia admin- have been effectively used to provide deep anesthesia assisting for dental assistants istered in the office, a surgical center, or a sedation and general anesthesia in the are available from the American Associa- hospital. The challenge for every dentist ambulatory setting.22-24 tion of Oral and Maxillofacial Surgeons is to formulate an anesthetic treatment For short cases such as third-molar and the California Association of Oral and plan to suit each patient’s need. When removal, endotracheal intubation is rarely Maxillofacial Surgeons. dentists are consistently able to do this, necessary when office-based general Third, state law mandates that all patients will no longer have to fear dental anesthesia is employed. However, because conscious sedation and general anesthesia treatment and our success as doctors and the patient’s protective airway reflex is ob- permit holders undergo a rigorous office humanitarians will be elevated to a new, tunded, care must be taken to protect the anesthesia evaluation every six years. The higher level. airway. Placement of a 4-x-4-inch gauze as office anesthesia evaluation was devel- a pharyngeal shield (throat pack) is useful. oped by the Southern California Society References 1. Dionne RA, Gordon SM, et al, Assessing the need for In cases where the dental procedure is of Oral and Maxillofacial Surgeons in the anesthesia and sedation in the general population. J Am Dent expected to last longer than an hour, or late 1960s and was subsequently incorpo- Assoc 129(2):167-73, 1998. when considerable water spray is going rated into the state Dental Practice Act. 2. Mission statement of the American Dental Society of Anesthesia, Chicago. to be used, the airway can be protected There are six components of the evalua- 3. Green NM, Anesthesia and the development of surgery with a laryngeal mask or by endotracheal tion. The first four involve the inspection (1846-1896). Anesthesia and Analgesia 58:5-12, 1979. intubation. of the office physical plant, emergency 4. American Society of Anesthesiologists, Definition of General Anesthesia and Levels of Sedation/Analgesia. ASA Regardless of the equipment and monitors, emergency Standards and Guidelines, Park Ridge, Ill, Oct 2001. technique employed, a dedicated person drugs, and records. The anesthetic team 5. American Dental Association, The Use of Conscious (other than the operator) must be present is then evaluated as common anesthetic Sedation, Deep Sedation and General Anesthesia in Dentistry. American Dental Association, Chicago, 1996. during a general anesthetic to manage the emergencies are simulated. Finally, an 6. American Academy of , Reference airway and monitor the patient. actual sedation or general anesthetic is Manual 1998-1999. American Academy of Pediatric Dentistry, observed. Chicago, 1998. 7. California Business and Professions Code Sec. 1646-1647.9 Safety Concerns 8. Clark MS, Brunick A, Handbook of Nitrous Oxide and Oxygen Ambulatory outpatient sedation and Other Options Sedation, CV Mosby, St Louis, 1999. general anesthesia in dentistry has an Not all patients are good candidates for 9. Haraguchi N, Furusawa H, et al, Inhalation sedation with sevoflurane: A comparative study with nitrous oxide. J Oral enviable safety record. Lytle and Stamper in-office sedation and general anesthesia. Maxillofac Surg 53(1):24-6, 1995. reported a mortality rate of seven deaths Patients with serious health conditions, 10. Bandrowsky T, Orr FE, et al, Desflurane for outpatient in 4.7 million office anesthetics adminis- young children with significant restorative general anesthesia in third molar extraction cases. J Oral Maxillofac Surg Feb 55(2):129-32. tered from 1968 to 1987 by Southern Cali- needs, and individuals who are physically 11. Koerner B, The father of mother’s little helpers. US News fornia oral and maxillofacial surgeons.25 A challenged, may be poor candidates for World Report December, 1999. similar survey of Massachusetts oral and office-based treatment. Some hospitals 12. Kaufman E, Hargreaves KM and Dionne RA, Comparison of oral triazolam and nitrous oxide with placebo and intravenous maxillofacial surgeons found no deaths in have dental equipment that can be moved diazepam for outpatient premedication. Oral Surg Oral Med 1.5 million office anesthetics during a five- into an operating room and encourage den- Oral Path 75(2):156-64, 1993. year period.26 tists to join their medical staffs. Patients 13. Baughman VL, Becker GL, et al, Effectiveness of triazolam, diazepam and placebo as preanesthetic medications. This exemplary safety record can be who could not otherwise have dental care -- Anesthesiology 71(2):196-200, 1989. attributed to several factors.27 First, as such as those with severe physical, mental, 14. Yagiela J, Personal communication, 2002. previously mentioned, the sedation and or psychological disabilities -- can receive 15. Brown B, Linter S, Monamine oxidase inhibitors and narcotic analgesics: A critical review of the implications for general anesthesia modalities used in the comprehensive dental care while anesthe- treatment. Br J Psychiatry 151:210-2 1987. dental community are generally reserved tized by the hospital’s anesthesia service. 16. Jaffe TB, Ramsey FM, Attenuation of Fentanyl-Induced

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Truncal Rigidity, Anesthesiology 56:562, 1983. 17. Dembo JB, The use of intravenous anesthesia and sedation technologies in oral and maxillofacial surgery. J Oral Maxillofac Surg 51(4):346-51, 1993. 18. Haas DA, Hauper DG, Ketamine: A review of its pharmacological properties and use in ambulatory anesthesia. Anesthesia Progress 39:61-8. 19. Borgeat A, Wilder-Smith OH, et al., Subhypnotic doses of propofol possess direct antiemetic properties. Anesth Analg 74:539-41, 1992. 20. Hubble AO, Methohexital sodium anesthesia for oral surgery. J Oral Surg 18:295, 1960. 21. Drummond-Jackson SL, A milestone in intravenous anesthesia. Brit Dent J 113:404, 1962. 22. Candeleria LM, Smith RK, Propofol infusion technique for outpatient general anesthesia. J Oral Maxillofac Surg 53(2):124-8, 1995. 23. Badrinath S, Avramov MN, et al, The use of a Ketamine- propofol combination during monitored anesthesia care. Anesthesia Analgesia 90: 858-62, 2000. 24. Toth E, A comparison of remifentanyl/midazolam with remifentanyl/propofol for monitored anesthesia care during extracorporal shockwave lithotripsy. Masters Thesis, University of Kansas, Department of Allied Health, Division of Nurse Anesthesia, 1998. 25. Lytle JJ, Stamper EP, The 1988 anesthesia survey of the Southern California Society of Oral and Maxillofacial Surgeons. J Oral Maxillofac Surg 47(8):834-42, 1989. 26. D’Eramo EM, Morbidity and mortality with outpatient anesthesia: The Massachusetts experience. J Oral Maxillofac Surg 57(5):531-6, 1999. 27. Dembo JB, Complications in anesthesia. In, Fonseca R, ed, Oral and Maxillofacial Surgery, 1st ed. WB Saunders, Philadelphia, 2000. To request a printed copy of this article, please contact/ Tim Silegy, DDS, 6226 E. Spring St., #315, Long Beach, CA 90815.

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Pediatric Oral Conscious Sedation

Tim Silegy, DDS, and Scott T. Jacks, DDS

abstract As the young indigent population of this state grows, access to dental care continues to be a problem. Studies show that children from poor families suffer from a higher caries rate than those from a higher socioeconomic class. The management of pain and anxiety with intravenous sedation or general anesthesia in the young, precooperative patient, can be a significant adjunct to the delivery of dentistry. However, because children in this demographic group frequently lack the financial resources necessary for these treatment modalities, they will either not receive the necessary care because they are deemed unmanageable or will have a traumatic experience causing them to become even more resistant to future dental care. This article demonstrates how oral conscious sedation can be a safe and cost-effective alternative to intravenous sedation and general anesthesia in facilitating dental care for children who could otherwise not be treated.

authors ccess to dental care for the before entering kindergarten.”1 Hence, the children of California has child’s first dental experience is frequently Tim Silegy, DDS, is a diplomate of the become an important is- unpleasant because it involves major American Board of sue for both the California restorative dentistry. Oral and Maxillofacial Dental Association and the Managing the dental needs of the Surgery. He maintains a ACalifornia Society of Pediatric Dentists. pediatric population imparts a unique chal- private practice in Long The 2000 surgeon general’s report on lenge to the dental practitioner. He or she Beach, Calif. Oral Health in America confirms the must not only be skilled at diagnosing and Scott T. Jacks, DDS, FACD, need for action in this area. It states that treating the deciduous and succedaneous has a private pediatric “dental caries is the single most common dentition, but also be able to assess and ad- dental practice in chronic childhood disease -- five times dress the emotional and behavioral status Southgate and Norwalk, more common than asthma and seven of children. Many prekindergarten children Calif. times more common than hay fever.”1 are not capable of sitting for protracted Disclosure The executive summary of the re- periods. This fact makes them poor candi- Dr. Silegy gives basic, port also states that “the social impact dates for restorative dental procedures and advanced, and pediatric of oral disease in children is substantial.” represents a troubling issue. These chil- life support lectures Nationally, “more than 51 million school dren, ranging in age from 2 to 4 years, are for CME Associates in Orange, Calif., and hours are lost each year to dental-related developmentally at a precooperative age.2 is the director of the illness. Poor children suffer 12 times more The typical attention span of such a young oral and maxillofacial restricted-activity days than do children child is four to eight minutes.3 In addition, surgery assistant’s from higher-income families. Pain and suf- many find restorative dentistry emotion- course sponsored fering due to untreated diseases can lead ally stressful; and research has shown by the California Association of Oral and to problems in eating and speaking and that children of this age, when placed in Maxillofacial Surgeons attending to learning.”1 Another significant emotionally stressful situations, tend to in Roseville, Calif. finding of the report is that “25 percent regress, further impeding the ability of the of poor children have not seen a dentist dentist to perform dentistry effectively.

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Some of these young patients with Frankl.4 should be deferred for two weeks from the extensive dental caries require general Wright’s system places children into cessation of symptoms.8 anesthesia to facilitate treatment. Others, one of three categories based upon their with no complicating medical conditions, behavior: Dental Evaluation can be ideal candidates for intravenous * Cooperative; Necessary dental procedures should sedation. IV sedation and general anes- * Lacking in cooperative ability; or be categorized based upon the anticipated thesia are expensive, ranging in cost from * Potentially cooperative. time needed for their completion. The hundreds to thousands of dollars, before Frankl’s behavior rating scale divides authors believe that the child whose dental a penny is spent restoring the mouth. In behavior into four categories: work can be completed in an hour or less many instances, these financial issues * Rating 1 -- definitely negative; makes the best candidate for oral seda- further block access to care. * Rating 2 -- negative; tion. Children requiring significantly more Oral conscious sedation is another, * Rating 3 -- positive; and chairtime might be better served by an IV significantly less expensive, option. An ap- * Rating 4 -- definitely positive. sedation, general anesthetic, or additional propriately trained and permitted dentist Some dentists develop their own scale appointments using oral sedation. (see Silegy and Kingston in this issue) can and use it to evaluate the behavior of Standardized treatment protocols that safely perform this procedure in the office. young children in the dental setting. No consider the child’s behavioral, medical, Children, who may not be able to tolerate matter what system a practitioner uses, the and dental evaluation can aid the practi- restorative procedures with nitrous oxide- essential issue is that he or she documents tioner in determining the best course of oxygen and local anesthesia alone, are preoperative behavior and considers it treatment. frequently ideal candidates. Oral sedation when formulating the treatment plan. enables the dentist to perform the neces- Agents and Techniques sary dental treatment with minimal stress Medical Evaluation Many agents and techniques have been to the patient and dental team. In some The medical condition of the pediatric used to sedate the pediatric patient.9,10 instances, it may not be the treatment of patient can have a profound effect on the The administration of oral sedative medica- choice; but when appropriate, oral sedation dental treatment plan. To be considered for tions is generally well-tolerated by children. may make the difference between treat- oral sedation in the dental office setting, While most agents are unpleasant to taste, ment and no treatment at all. children should be free of systemic disease when mixed with sweetened drink powders (ASA Class I) or have a well-controlled or juice, they are generally palatable to Preoperative Evaluation medical condition such as mild asthma or patients, particularly when thirsty from Not all children are good candidates diabetes (ASA Class II). preoperative fasts. for oral sedation. Successful manage- Because most cases of morbidity and While effective, oral sedation is much ment of pediatric dental patients requires mortality associated with pediatric oral less predictable than intravenous sedation. the dentist to have an understanding of conscious sedation involve airway and/ When a sedative agent is administered in- age-dependent behavior, medical condi- or respiratory complications, it is impera- travenously, the plasma concentration rises tions that could complicate sedation, and tive that special attention be paid to these quickly to elicit an immediate dose-de- the complexity of the anticipated dental areas.5 The most common acute medi- pendent response. The same agent, when treatment. cal condition affecting young children is administered orally, may be subject to deac- the upper-respiratory tract infection or tivation in the highly acidic environment of Behavioral Evaluation common cold. Preschool-aged children the stomach. Upon passing into the small During the initial exam, it is important suffering from an upper-respiratory tract intestine, there is a generally rapid uptake for the dentist to evaluate and classify infection are more prone to complications of the agent into the portal circulation. In behavior so that an estimate of the child’s because they frequently are obligate nose the liver, a significant portion is metabo- cooperative ability can be determined. breathers.8 The hypersecretion and edema lized by the cytochrome p-450 complex This determination will assist the treating associated with an upper-respiratory tract (phase I metabolism), conjugated with dentist in deciding whether the patient is a infection can dramatically diminish their glucuronic acid (phase II metabolism), and candidate for nonpharmacologic interven- ability to keep their airway clear, especially transported to the kidneys, where it is tion, oral conscious sedation, IV sedation, after having received a sedative and local excreted in the urine.11 Consequently, after or general anesthesia. Numerous systems anesthetic. Additionally, nitrous oxide- a considerable delay, only a fraction of the have been developed to accomplish this oxygen administered via a nasal hood, will administered agent enters the plasma. task. Two prominent classification systems have little effect on the child with nasal A list of agents commonly used for pe- have been developed by Wright and congestion.7 In this instance, treatment diatric oral conscious sedation in dentistry

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is given in Table 1. Of the agents listed, 75 to 100 mg/kg have also been suggested. mix with juice for oral administration. It is chloral hydrate has been and continues to These higher doses may render patients also available premixed with cherry syrup. be a popular sedative.12-14 Developed in incapable of independently maintaining Studies suggest that it is the ideal oral 1832 by Leibig, it is currently available in their airways and unable to respond ap- sedative.26-34 Normal dosing is 0.25 to 0.5 capsule, syrup, and suppository form. The propriately to verbal command, as required mg/kg with a duration of 30 to 45 minutes. sedative properties of chloral hydrate are by the California Dental Practice Act.16 An Exceptionally anxious children may require attributed to the active metabolite trichlo- antihistamine may be given in conjunction dosing up to 1 mg/kg not to exceed a 20 roethanol.15 An alcohol, it follows zero-or- with chloral hydrate to reduce the inci- mg dose. Unlike diazepam, midazolam has der kinetics and as such, has no definitive dence of nausea and vomiting.17-19 little if any hangover effect, allowing for a half-life. Consequently, the duration of the As a group, benzodiazepines are the full recovery prior to discharge. sedative effect can be highly variable and safest and most effective sedatives avail- Another benzodiazepine, triazolam as unpredictable when compared to agents able. Their successful use in the pediatric been used to sedate children.23,24 To date, that follow first-order kinetics. population is well-documented in the it has not been approved by the Food and The duration of the sedative effect can medical and dental literature.20-25 Ben- Drug Administration for use as a sedative. be significantly longer than the work- zodiazepines act centrally at the gamma- In cases of overdosage, benzodiaz- ing time. Patients who may have moved amino-butyric-acid receptor in the limbic epines are easily reversed by flumazenil 0.2 excessively at the end of a procedure system to produce anxiolysis and profound mg IV.35,36 Some advocate injecting fluma- may become quite somnolent when the amnesia. The two principal agents pres- zenil sublingually in cases of emergency. A stimulation of treatment has ceased. This is ently used to orally sedate children are search of the literature revealed no studies especially true for patients having received diazepam and midazolam. Valium is typi- to support this practice. chloral hydrate and is a significant disad- cally crushed and mixed with juice for oral The sedative and analgesic proper- vantage in the outpatient setting, where administration. It is administered in a dose ties of opioids make them desirable seemingly alert patients are discharged of 0.5 mg/kg and has a duration of 30 to 45 agents for oral sedation. When bound into their parent’s care. minutes. A disadvantage of diazepam is an to specific opioid receptors in the spinal Broad dosing regimens for chloral hy- extended half-life secondary to the active cord and central nervous system, opioids drate have been reported. While variability metabolite oxazepam, which can render attenuate pain and produce sedation and in patient response is possible, a dose of 25 the patient sluggish for up to 48 hours. dose-dependent respiratory depression. to 50 mg/kg, not to exceed a total dose of Midazolam is twice as potent as diaz- Meperidine hydrochloride is frequently 1 g provides adequate sedation. Doses of epam and water-soluble, making it easy to used as an oral sedative. Administered at

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a dose of 1 to 2 mg/kg, it produces anal- gesia, sedation, and euphoria. Because of the frequently encountered side effects of nausea and vomiting and respiratory de- pression, meperidine is seldom adminis- tered alone. The “DPT cocktail,” a mixture of Demerol (meperidine), Phenergan (promethezine) and Thorazine (chlor- promazine), has been used extensively by emergency physicians in hospitals and, to a lesser extent, by pediatric dentists in the dental office.37,38 Chlorpromazine, a neuroleptic, increases the depth of seda- tion without increasing the incidence of respiratory depression. It is also a potent status can be achieved. Table 2 lists current used, care should be taken not to exceed a antiemetic. Promethezine also has seda- American Society of Anesthesiologists total dose of 4 mg/kg of body weight.42,43 tive properties, decreases the incidence preoperative fasting guidelines. Pediatric Prior to the dentist’s beginning treatment, of nausea, and dries the mouth. While patients should be scheduled to arrive at he or she should protect the airway with a generally safe, the DPT cocktail has been the office one hour prior to the anticipated gauze throat pack or rubber dam; and aux- associated with seizures and may render a treatment time. The treating doctor should iliary staff should be vigilant in suctioning. child unresponsive.39 quickly reassess the patient by evaluat- At the conclusion of the procedure, the As a group, antihistamines are very ing the airway, listening to the heart and clinician must be sure that the maximum safe agents to use on children.40 Blockade lungs, recording baseline vital signs, and effect of the sedative has passed prior to of serotonin receptors by antihistamines confirming NPO status. A written consent the cessation of monitoring. If extractions in the central nervous system produces explaining the anticipated dental treat- were carried out, gauze hemostasis should a sedative-like effect. Although they lack ment, the reason for utilizing sedation, the be confirmed. Prior to discharge, postoper- anxiolytic, amnestic, and analgesic proper- use of restraints, and the risks, complica- ative vital signs should be close to baseline; ties, antihistamines cause drowsiness and tions, treatment alternatives, and expected and the patient must be able to maintain have antiemetic and antisialogogue effects. outcomes should be signed by a parent or his or her oxygen saturation on room air. Commonly used antihistamines include legal guardian prior to treatment. The child should be alert, oriented, and promethezine and hydroxyzine adminis- The oral sedative should then be able to ambulate with minimal assistance. tered in a dose of 0.5 to 1 mg/kg. administered and the patient observed Finally, detailed written and verbal postop- The patient evaluation mentioned by trained staff. As the patient becomes erative instructions should be given to the earlier can aid the dentist in formulat- drowsy, he or she should be casually walked parents. ing a pharmacologic treatment plan. or carried to the treatment area. Oxygen This plan might make use of one or a should be administered via nasal mask or Safety combination of drugs. Studies show that nasal canula. If nitrous oxide-oxygen is to Anesthetic emergencies occurring in the failure rate (being unable to initiate be used, it should be titrated to effect via a children almost always involve airway and/ or complete treatment) of oral sedation scavenged nasal hood system (See Mal- or respiratory compromise. Because of can be as high as 40 percent and that amed in this issue). Adjuncts to pharma- their disproportionately large , pro- the regimen used successfully for one cologic anxiolysis such as stuffed animals, liferation of lymphoid tissue, and large ton- appointment may not be effective for ceiling-mounted televisions, and head- sils, children breathe most readily through the next.41 Because repeat doses of oral phones are effective and can help promote their noses. During dental treatment, the sedatives are contraindicated at the same cooperative behavior. most common causes of airway obstruc- appointment, it is important to have an As the child settles into his or her envi- tion in a child are occlusion of the posterior alternate treatment plan available. ronment, a blood pressure cuff, precordial oropharynx with the tongue and obstruc- stethoscope, and pulse oximetry probe can tion of the nares with the nitrous hood.7 It Technique be placed and vital signs recorded. Local is therefore critical to observe patients for When feasible, it is advantageous to se- anesthesia should then be administered adequate air exchange at all times. date children in the early morning because slowly with a 30-gauge needle. If 2 percent To avoid positional asphyxiation, as a more reliable NPO (nothing by mouth) lidocaine with epinephrine 1:100,000 is much as practical, the child’s head position

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19. Robbins MB, Chloral hydrate and promethezine as should be maintained in the sniffing posi- problem, for the foreseeable future, the premedicants for the apprehensive child. J Dent Child 34:327- tion with the head extended. If obstruc- major responsibility for restoring these 31, 1967. tion is suspected, the tongue should be decayed teeth will fall on the dedicated 20. Badalaty NM, Houpt MI, et al, A comparison of chloral pulled forward in the mouth, the posterior dentists of California. If the dental needs hydrate and diazepam sedation in young children. Pediatr Dent oropharynx suctioned, and the nasal hood of the pediatric population are to be ad- 12:33-7, 1990. 21. Saarnuvaara L, Kindgreb L, et al, Comparison of chloral repositioned. dressed safely and effectively, it is vital hydrate and midazolam by mouth as premedicants in children Apnea in the absence of airway ob- that dentists who treat children receive undergoing otolaryngological surgery. Brit J of Aenes 61:390, struction is a complication of oral sedation appropriate training in oral conscious 1988. rarely seen with normal dosing. When it sedation on a regular basis. 22. Scott TR, Kenneth RW, et al, A randomized double blind does occur, it is easily managed with stimu- trial of chloral hydrate/hydroxyzine versus Midazolam/ References acteominophen in the sedation of pediatric dental lation, positive pressure ventilation, and/or outpatients. J Dent Child 63:95-100, 1996. reversal of the sedative agent. 1. Oral Health in America: A Report of the Surgeon General, Executive Summary, Dept. of Health & Human Services, U.S. 23. Stopperich DS, Moore PA, et al, Oral triazolam Public Health Service. 05/26/00: 8 – 9 pretreatment for intravenous sedation. Anesth Prog 40:117-21, Summary http://www.nider.nih.gov/sgr/execsumm.htm 1993. Thousands of children are sedated safe- 2. Blake FG, Immobilized youth -- a rationale for supportive 24. Quarnstrom FC, Milgrom P, Clinical experience with oral nursing intervention. Am J Nurs 69: 2364, 1969. triazolam in preschool children. Anesth Pain Control Dent ly by dentists daily in the United States. 1:157-9, 1992. While rare, morbidity and mortality in 3. Steiner JF, Comprehensive Review of Pediatric Dentistry. American Academy of Pediatric Dentistry, 2002, p 132. 25. Dundee JW, Advantages and problems with benzodiazepine pediatric patients receiving oral conscious 4. McDonald, Avery, eds, Dentistry for Child and Adolescent, sedation. Proceedings of the Sixth International Dental sedation does occur. Retrospective analysis 6th ed. CV Mosby, Philadelphia, 1994, p 37 Congress on Modern Pain Control, Washington DC, May, 1991. has demonstrated that most mishaps can 5. Motoyama EK, Respiratory physiology in infants and 26. Dock M, Reynolds NM, et al, Orally administered children. In, Motoyama EK, Davis PJ, eds, Smith’s Anesthesia midazolam as a sedative agent in pediatric dental patients. generally be attributed to four things:44,45 Proceedings of the Sixth International Congress on Modern * Inadequate preoperative evaluation; for Infants and Children. CV Mosby, St Louis, 1996. 6. Kaplan RF, Grave SA, Anatomic and physiologic differences Pain Control, Washington DC, 1991. * Lack of knowledge concerning the of neonates, infants and children. Seminars in Anesthesia 27. Gallardo F, Cornejoo G, et al, Oral midazolam as pharmacology of drugs employed; 3:1-14, 1984. premedication for the apprehensive child before dental * Inadequate monitoring during the 7. Litman RS, Kottra JA, et al, Upper airway obstruction during treatment. J Clinic Pediatr Dent 18:123-7, 1994. midazolam/nitrous oxide sedation in children with enlarged 28. McMillan CO, Spahr-Schopferl A, et al, Premedication of procedure; and children with oral midazolam. Canadian J Anesthesiol 39:545, * Lack of training in the management tonsils. Pediatric Dentistry 50:318-20, 1998. 8. Tait AR, Knight PR, The effect of general anesthesia on 1992. of emergencies. upper respiratory infections in children. Anesthesiology 29. Vetter TR, A comparison of midazolam, diazepam and Competency in the administration of 67:930, 1987. placebo as oral anesthetic premedicants in younger children. J oral sedation is necessary for dentists who 9. Moore P, Houpt M, Sedative drug therapy in pediatric Clinical Anesthesiol 5:58-61, 1993. dentistry. In, Dionne RA, Phero JC, eds, Management of Pain 30. Dionne R, Oral midazolam syrup: a safer alternative for choose to treat children on a regular basis. pediatric sedation. Compendium 20:221-30, 1999. In California, advanced training programs and Anxiety in Dental Practice. Elsevier, New York, pp 239-66, 1991. 31. Smith BM, Cutilli BJ, et al, Oral midazolam: pediatric in pediatric dentistry are offered at Loma 10. Grimes JG, Oral premedication in children. Anesth Anal conscious sedation. Compendium, 19:586-92, 1988. Linda University, the University of Cali- 41:201-2, 1962. 32. Litman RS, Berkowitz RJ, Levels of consciousness and fornia at Los Angeles, the University of 11. Stoelting RK, Pharmacology and physiology. In Anesthetic ventilatory parameters in young children during sedation with Practice, 2nd ed. JB Lippincott Co, Philadelphia, 1987. oral midazolam and nitrous oxide. Archiv Pediatr Adolescent California at San Francisco, and the Uni- Med 150:671-5, 1996. versity of Southern California. Continuing 12. Malis DJ, Burton DM, Safe pediatric outpatient sedation: the chloral hydrate debate revisited. Otolaryngol Head Neck 33. Hennes HM, Wagner V, et al, The effect of oral midazolam education programs designed to fulfill the Surg 116(1):53-7, 1997. on anxiety of preschool children during laceration repair. Ann educational requirements mandated by 13. Dunkan WK, De Ball S, et al, Chloral hydrate sedation: a Emerg Med 19:1006-9, 1990. the state legislature for an oral conscious simple technique. Compendium 15:886-8, 1994. 34. Kraft TC, Kramer N, et al, Experience with midazolam as 14. Moore PA, Therapeutic assessment of chloral hydrate sedative in the treatment of the uncooperative child. J Dent sedation permit are taught by the facul- Child 60:295-9, 1993. ties of UCLA, UCSF, Loma Linda, and premedication in pediatric dentistry. Anesthesia Progress 31:191-6, 1984. 35. Holloway AM, Logan DA, The use of Flumazenil to reverse CME Associates. 15. Marshall EK, Owens AH, Absorption, excretion and diazepam sedation after endoscopy. Eur J Anaesthesiol suppl In the coming years, California must metabolic rate of chloral hydrate and trichloroethanol. Bulletin 2:191-4, 1988. face and solve the growing issue of access Johns Hopkins Hospital 95:1-18, 1954. 36. Moore, PA, Flumazenil in Intravenous Conscious Sedation 16. California Business and Professions Code Sec. 1646-1647.9 with Diazepam, Multicenter Study Group II: Reversal of central to care for the young children of the state. benzodiazepine effects by flumazenil after intravenous With dental caries being the single most 17. Houpt M, Koenigsberg S, et al, Comparison of chloral hydrate with and without promethezine in the sedation of conscious sedation with diazepam and opioids Clin Ther common childhood disease, the challenge young children. Pediatr Dent 4:41, 1985. 14:910-23, 1993. will be daunting. While water fluorida- 18. Needleman HL, Joshi A, et al, Conscious sedation of 37. Smith C, Rows RD, et al, Sedation of children for tion and other preventive modalities may pediatric dental patients using chloral hydrate, hydroxyzine catheterization with an ataractic mixture. Can Anaesthet Soc J 5:35, 1958. make significant inroads into solving this and nitrous oxide -- a retrospective study of 382 . Pediatr Dent 17(7):424-31, 1995. 38. Saravia ME, Currie WR, et al, Cardiopulmonary parameters may 2003 417 pediatrichead

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during meperidine, promethezine, and chlorpromazine sedation for pediatric dentistry. Anesthesia Progress 34:92, 1987. 39. Smudski JW, Sprecher RL, et al, Convulsive interactions of promethezine, meperidine and lidocaine. Arch Oral Biol 9:595-600, 1964. 40. Land LL, An evaluation of the efficacy of hydroxyzine (Atarax, Vistaril) in controlling the behavior of child patients. J Dent Child 32:253, 1965. 41. Dembo J, Pediatric Considerations in Office Anesthesia. in Oral and Maxillofacial Surgery Knowledge Update, vol 1, 1994, pp 105-11. 42. Moore PA, Prevention of local anesthesia toxicity, J Am Dent Assoc 123:60-4, 1992. 43. Goodson JM, Moore PA, Life-threatening reactions after pedodontic sedation: an assessment of narcotic, local anesthesia and antiemetic drug interaction, J Am Dent Assoc 107:239, 1983. 44. Cote CJ, Karl HW, et al, Adverse sedation events in pediatrics: analysis of medications used for sedation. Pediatrics 106:633-44, 2000. 45. Cote CJ, Karl HW, et al, Adverse sedation events in pediatrics: a critical incident analysis of contributory factors. Pediatrics 105:805-14, 2000. To request a printed copy of this article, please contact/ Tim Silegy, DDS, 6226 E. Spring St., #315, Long Beach, CA 90815.

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Current Concepts in Acute Pain Management

Mai-Phuong Huynh, DDS, and John A. Yagiela, DDS, PhD

abstract Analgesics most commonly prescribed in dentistry for acute pain relief include the nonsteroidal anti-inflammatory drugs, acetaminophen, and various opioid-containing analgesic combinations. The NSAIDs and presumably acetaminophen act by inhibiting cyclooxygenase enzymes responsible for the formation of prostaglandins that promote pain and inflammation. Opioids such as codeine, hydrocodone, and oxycodone stimulate endogenous opioid receptors to bring about analgesic and other effects. Numerous clinical studies have confirmed that moderate to severe pain of dental origin is best managed through the use of ibuprofen or another NSAID whose maximum analgesic effect is at least equal to that of standard doses of acetaminophen-opioid combinations. If an NSAID cannot be prescribed because of patient intolerance, analgesic preparations that combine effective doses of an orally active opioid with 600 to 1,000 mg of acetaminophen are preferred in the healthy adult. On occasion, prescribing both an NSAID and an acetaminophen-opioid combination may be helpful in patients not responding to a single product. In all cases, however, the primary analgesic should be taken on a fixed schedule, not on a “prn” (or as needed) basis, which only guarantees the patient will experience pain.

authors he prescription illustrated in rizes how these drugs may be prescribed to Mai-Phuong Huynh, Figure 1 has most likely been best advantage for acute pain relief. DDS, is a dental written more frequently in den- anesthesiology tistry for the management of History resident in the Division moderate to severe pain (as may The first “prescription” for pain man- of Diagnostic and accompany the surgical extraction of third agement can be traced back 2,400 years, Surgical Sciences at the T University of California molars) than any other during the past when Hippocrates suggested using juices of at Los Angeles School of three decades and remains highly popular the poplar and willow bark to alleviate the Dentistry. today. Nevertheless, modern guidelines pain of childbirth. Millennia later, it was for acute pain management identify three found that these juices contained the com- John A. Yagiela, DDS, PhD, is professor and significant problems involving this pre- pound salicin. In 1853, Charles Frederich chair of the Division of scription with respect to the typical dental Gerhardt synthesized aspirin by treating Diagnostic and Surgical patient. In addressing these problems, this sodium salicylate (a simple derivative of Sciences at UCLA School paper reviews the currently available oral salicin) with acetyl chloride. Aspirin was of Dentistry. analgesics used in dentistry and summa- introduced clinically in 1899 by Heinrich

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Role of Cyclooxygenase and encodes COX-1. This COX-3 is found in the Prostaglandins brain and is inhibited by clinically achiev- Tissue damage stimulates at the site able concentrations of acetaminophen.3 of injury the release of inflammatory An additional form of COX that is induced mediators such as prostaglandins, kinins, with high concentrations of NSAIDs and leukotrienes, substance P, and histamine. is selectively inhibited by acetaminophen These mediators help initiate and subse- may be derived from the COX-2 gene.4 quently magnify nociceptive impulses that Role of Endogenous Opioids are transmitted to the central nervous Nociceptive pathways in the central system for the perception of pain. Of these nervous system are subject to modulation mediators, prostaglandins are especially by neurons that release inhibitory trans- important in sensitizing peripheral neu- mitters at synaptic sites important for the rons to the local stimulus. Prostaglandins perception of pain. Brain sites involved Dresser of the Bayer Company in Germany are also synthesized in the spinal cord and in affective responses to pain are also and remains one of the most common possibly higher brain centers in response inhibited. Endogenous opioid peptides that remedies for acute pain. to nociceptive impulses and enhance pain stimulate specific opioid receptors play a Opioid use dates back even further, to sensitivity by recruiting additional second- pivotal role in blunting pain. Evidence has the early civilizations of Persia, Egypt, and ary neurons that respond to the primary accumulated in recent years that peripheral Mesopotamia. A Sumerian text from 4,000 stimulus. nerves in inflamed tissues also contain opi- B.C. was the first to refer to opium derived Aspirin and related nonsteroidal anti- oid receptors whose activation can produce from the poppy plant. In 1805, Wilhelm inflammatory drugs work at the site of tis- analgesia.5 Sertürner isolated morphine from opium, sue damage, the spinal cord, and/or higher Morpine and related opioid analgesics giving clinicians for the first time a chemi- brain centers to prevent prostaglandin exert most of their pharmacologic ef- cally pure, highly effective analgesic. formation by inhibiting cyclooxygenase, fects by stimulating the µ opioid receptor. Continued advances in the development or COX, activity. With the partial excep- In addition to relieving pain, µ-receptor of aspirin-like and morphine-like drugs have tion of acetaminophen, which has minimal stimulation can cause a tranquil euphoria, made available a broad spectrum of agents anti-inflammatory effects in most settings, nausea and vomiting, and constipation. to manage acute pain. In addition, there has these drugs exert a combination of anal- In overdose, respiratory depression is the been a new understanding of how these gesic, antipyretic, and anti-inflammatory primary concern; chronic use can lead to analgesics should be used for optimal pain effects. physical and psychological dependence. relief in the outpatient setting. Tissue COX exists in two well-known Pentazocine, nalbuphine, and related subtypes: COX-1 and COX-2. COX-1 is a opioid agonist-antagonists promote anal- Pain and Analgesia constitutive form that supports hemosta- gesia by stimulating the ? opioid receptor. The International Association for the sis (where synthesis of the prostaglandin Analgesic and respiratory depressant effects Study of Pain defines pain as “an unpleas- analogue thromboxane A2 increases plate- are similar to those elicited by morphine ant sensory and emotional experience let degranulation and adhesion), stomach in normal clinical doses; however, a ceiling arising from actual or potential tissue mucosal integrity (where synthesis of pros- effect limits these responses in overdose. damage or described in terms of such dam- taglandins protects against acid damage), Sedation is a common side effect of the age.”1 Pain can be separated into two broad and kidney function (where prostaglandins agonist-antagonists, but stimulation of ? re- categories: acute and chronic. Acute pain help regulate normal renal blood flow). ceptors is more likely to produce dysphoria lasts from seconds to days. It generally has COX-2 is a largely inducible form whose than euphoria, and psychotomimetic reac- a known cause and subsides with removal synthesis is activated in damaged or stimu- tions are common with large doses. Physical of the stimulus and healing. Acute pain lated tissues and leads to the formation of dependence is possible but less problematic may be associated with heightened arousal, pro-inflammatory prostaglandins. COX-2 with ? agonists. Precipitation of an acute leading to tachycardia, tachypnea, and plays a major role in inflammation, pain, opioid withdrawal reaction may occur when anxiety. In contrast, chronic pain typically and fever. It is also constitutively active in pentazocine or nalbuphine is administered lasts from months to years. The body has regulating renal blood flow.2 to an opioid-dependent individual. become adapted to this level of pain, and There is increasing evidence that one often there is no increased sympathetic or more additional subtypes of COX may Nonsteroidal Anti-Inflammatory Drugs response. Chronic pain is associated with exist. A new COX-3 has been described (Including Acetaminophen) depression and decreased function. that is produced by the same gene that As the prototypical NSAID, aspirin

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remains a standard against which other profen in analgesic onset and peak effect immunosuppression; the clinical signifi- orally active analgesics are compared. It but has a longer duration of action.11 A cance of these findings for is relatively selective for COX-1 and is similar comparison holds for 440 mg of remains unknown.17,18 therefore prone to causing gastric bleeding naproxen sodium compared with 400 mg Morphine, the prototypical opioid and ulceration, especially with high doses of ibuprofen.12 Diclofenac, ketoprofen, analgesic, is rarely prescribed orally for the and chronic use. Aspirin is unique in that it flurbiprofen, meclofenamate, and diflu- management of acute pain because most acetylates the COX enzyme. This property, nisal are additional NSAIDs with analgesic of the drug is metabolized in the liver plus the drug’s relative COX-1 selectivity activity in the dental setting similar to that before it can reach the systemic circulation. and the inability of platelets to synthesize of ibuprofen or naproxen. Fenoprofen is Meperidine and many other opioids have new COX, provides the basis for the use of also approved for the management of acute similar problems with the oral route. The low-dose aspirin to prevent thromboem- pain, but its slow absorption retards the three most commonly used opioids for bolic heart attack and stroke in susceptible onset of analgesia. , an NSAID oral administration are codeine, hydroco- patients. Typical doses of 325 to 650 mg commonly used for parenteral administra- done, and oxycodone. These agents have a encompass most of aspirin’s analgesic tion, is restricted in its oral dosage form high oral:parenteral efficacy ratio, in part dose-response curve in the average adult. to patients who have already received the because a fraction of each drug is con- Acetaminophen’s analgesic and anti- drug by injection. Lastly, etodolac is a well- verted by the hepatic enzyme cytochrome pyretic properties are comparable to those tolerated NSAID; however, it has not been P450 2D6 (CYP2D6) to a much more of aspirin. However, it does not elicit gas- proved superior to aspirin for relieving active metabolite (codeine?morphine, trointestinal irritation or prolong bleeding, pain of dental origin. hydrocodone?hydromorphone, which are hallmarks of aspirin use. Acute The introduction of selective COX-2 oxycodone?oxymorphone) and released toxicity is minimal unless an overdose inhibitors has allowed specific targeting of into the bloodstream.19 About 5 percent to occurs, which may lead to hepatotoxicity. inflammatory prostaglandin production 10 percent of Caucasians and 1 percent to Analgesia by acetaminophen in the average while minimizing adverse side effects such 3 percent of African-Americans and Asians adult becomes readily measurable at a dose as gastrointestinal ulceration and bleed- have a polymorphic gene for CYP2D6 that of 300 mg and plateaus at 1,000 mg.6 ing problems.13 Clinically available COX-2 cannot support these conversion reac- Ibuprofen was the first NSAID to dem- inhibitors include rofecoxib, celecoxib, and tions. In the case of codeine, no analgesia onstrate analgesic superiority to aspirin. A valdecoxib. As yet, valdecoxib has not been is obtained, nor are such dose-dependent 400 mg dose of ibuprofen has been shown approved for the treatment of acute pain side effects as constipation or respira- to have a greater peak analgesic effect and (although recent studies indicate it has tory depression. On rare occasions, oral a longer duration than 600 to 1,000 mg strong potential for such use).14 Rofecoxib methadone may be prescribed for anal- of aspirin or acetaminophen, or 60 mg of enjoys two advantages over celecoxib and gesia. It is chemically unrelated to the codeine, and at least comparable efficacy to valdecoxib in that its duration of action aforementioned opioids and requires no traditional opioid analgesic combinations is sufficiently long to permit single daily metabolic conversion for its opioid action. (Figures 2a and b).7,8 One meta-analysis dosing, and it is not contraindicated in pa- Propoxyphene is structurally related to has suggested there is a dose-dependent tients with a history of sulfonamide allergy. methadone but is a much weaker analgesic. increase in analgesia with ibuprofen up to In a dose of 50 mg, rofecoxib is comparable At best, 100 mg of propxyphene napsylate 800 mg.9 However, the published source to 400 mg of ibuprofen in onset and peak is equivalent to 60 mg of codeine. from which the statistically analyzed data pain relief.15,16 Tramadol is an analgesic with two were obtained for this assertion actually complementary mechanisms of action. It revealed little analgesic improvement with Opioids and Related Agents is a weak µ-receptor agonist, imbuing the doses beyond 400 mg.10 It is likely that the In contrast to NSAIDs, opioids do not drug with opioid-like activity. In addition, principal effect of prescribing doses of ibu- have an obvious ceiling effect for analgesia. tramadol inhibits the reuptake of norepi- profen larger than 400 mg for pain relief is Thus, increasing the dose increases the nephrine and 5-hydroxytryptamine, an that the duration of maximum analgesia is pain relief. Unfortunately, opioids cause antidepressant-like action. Because of its prolonged. undesirable side effects that limit their weak opioid activity, tramadol exhibits less Naproxen, an NSAID structurally dosing, especially in the outpatient setting. respiratory depression, drug dependence, related to ibuprofen, has a half-life of about These adverse effects include nausea and and other side effects commonly associated 13 hours, which allows for less frequent vomiting, constipation, sedation, and, in with opioid use. However, studies have dosing compared to ibuprofen (half-life of large doses, respiratory depression. Some shown that relief of acute oral surgery pain two hours).6 A 220 mg dose of naproxen opioids (e.g., morphine and codeine) also with 50 mg of tramadol is similar to that of sodium is equivalent to 200 mg of ibu- cause anti-inflammatory effects and even 60 mg of codeine but less than that of a full

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Figure 2a. Pain relief after removal of impacted third molars. Data from Cooper SA, Figure 2b. Pain rPain relief after removal of impacted third molars. Data Engel J, et al, Analgesic efficacy of an ibuprofen-codeine combination. Pharmacotherapy from Forbes JA, Kehm CJ, et al, Evaluation of ketorolac, ibuprofen, acetaminophen, 2:162-7, 1982. and an acetaminophen-codeine combination in postoperative oral surgery pain. Pharmacotherapy 10(suppl 6, part2):94S-105S, 1990. (Slightly negative pain intensity difference scores for placebo after two hours are not shown in the graph.) therapeutic dose of codeine in combination to combine two (or more) drugs with dif- phen and the NSAIDs act on the same or with aspirin or acetaminophen. Tramadol ferent mechanisms of action. The combina- different prostaglandin pathways involved with acetaminophen may be a suitable tion of acetaminophen or an NSAID with in nociception. choice for patients who do not tolerate an opioid allows for increased analgesia Caffeine is an analgesic adjuvant that NSAIDs or opioid analgesics well.20 because the drugs act through dissimilar exerts no analgesic action by itself in The agonist-antagonist pentazocine mechanisms.21 Because they also have humans but can enhance the potency of is another alternative to the codeine-like dissimilar side effects, summation of the such drugs as acetaminophen, aspirin, and opioids. A dose of 50 mg pentazocine is intensity of these effects does not occur. ibuprofen. In the case of ibuprofen given approximately equianalgesic as 60 mg of Combining an NSAID with another after third-molar surgery, the analgesic po- codeine. Other agonist-antagonists are not NSAID, or an opioid with another opi- tency of 100 to 200 mg doses is increased available in oral dosage forms. oid, provides no such benefit. In the case more than twofold by 100 mg of caffeine.25 of NSAIDs, the maximum pain relief is There are few data, however, to suggest Combination Analgesics already achieved by using a fully effective that caffeine can improve the analgesic No analgesic agent for oral admin- dose of a single agent. The combination effect of “ceiling” doses of NSAIDs or acet- istration is currently available that can can only produce increased adverse effects. aminophen.26 relieve all intensities of acute pain. The With opioids, the increased analgesia, Adverse effects of combination anal- NSAIDs, acetaminophen, and the opioid which could also have been obtained by gesics include those for each drug in the agonist-antagonists exhibit a ceiling effect using a larger dose of a single drug, is ac- combination. In addition, the chronic use for analgesia in that no greater pain relief companied by heightened adverse effects of aspirin, phenacetin (an acetaminophen can be obtained by increasing the dose that make such combinations intolerable. analogue), and caffeine, as once commonly beyond a certain limit. In the case of the Some practitioners prescribe acetamin- formulated in the “APC” tablet, has long morphine-like opioids, dose-dependent ophen with an NSAID for postoperative been associated with end-stage kidney toxicity restricts the analgesic effect that pain control. Clearly, if acetaminophen is disease. The simultaneous use for several can usually be obtained. In fact, standard insufficient by itself, then an NSAID with a days of an acetaminophen-opioid prepara- doses of opioids (e.g., codeine 30 to 60 mg, stronger analgesic effect may produce more tion and an NSAID has not been linked to hydrocodone 5 to 10 mg, oxycodone 5 to pain relief than can acetaminophen alone. increased renal toxicity. 10 mg) produce pain relief for dentistry It is unclear, however, if adding acetamino- Precautions and Drug Interactions that only approaches the analgesia of two phen to any NSAID already being taken at Adverse responses to analgesics are aspirin tablets (650 mg, see Figure 2). a ceiling analgesic dose provides any ben- more likely to occur in patients who have A strategy commonly used to enhance efit.22-24 Resolution of this question may certain medical conditions or are taking the analgesic benefit of oral medication is ultimately depend on whether acetamino- specific drugs. In the case of NSAIDs, all

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such drugs (including the COX-2-specific patient with an ulcer history, such drugs Severe inflammatory bowel disease is also agents) should be avoided in any patient are best avoided in individuals with an a contraindication to opioid use. Patients who has exhibited an allergic-like (ana- existing or recent ulcer because COX-2 is with a history of opioid drug abuse present phylactoid) reaction, such as urticaria, expressed locally during the healing phase. a special set of issues. These patients tend angioneurotic edema, bronchial asthma, Other conditions in which NSAIDs are to have a relatively low pain threshold, and acute hypotension, to any NSAID.6 It not recommended include pregnancy in which may be coupled with a relatively is believed that inhibition of COX in these the second and third trimester (possible high tolerance to opioids. Consultation patients may result in overproduction premature closure of the ductus arteriosus, with the patient’s physician is advised to of leukotriene mediators of anaphylaxis. excessive bleeding, or depressed uterine help balance the need for effective anal- NSAID intolerance is also particularly contractions during labor and delivery) gesic medication against the concern that common in patients with rhinitis, nasal and congestive heart failure or significant such medication may trigger addiction polyps, and asthma for which systemic renal impairment (possible fluid retention). relapse. (It should be noted that there is an corticosteroids must be used to control The use of aspirin in children may trigger extremely low incidence of drug addiction bronchospasm. Patients with bleeding Reye’s syndrome in the presence of a viral when short courses of opioids are given for disorders or platelet deficiency, or with a infection and is best avoided in pediatric analgesia to patients without a history of history of gastrointestinal inflammatory and adolescent patients.27 drug abuse.28) or ulcerative disease, should not receive Opioid analgesics are problematic in Geriatric patients often exhibit dimin- NSAIDs with COX-1 activity. Although patients with impaired respiration, as ished clearance of analgesic medications, it is probably safe to prescribe a short may accompany advanced emphysema increased plasma concentrations of free course of a COX-2-selective inhibitor in a or poorly controlled myasthenia gravis. drug, and increased pharmacologic effects.

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There is also a heightened risk for drug are effective for this level of discomfort; ery day for three days, to be approximately interactions since many elderly patients they are also inexpensive and sold over the 15 times that of 800 mg ibuprofen (four are already taking multiple medications, in- counter. Patients who have purchased spe- 200 mg tablets), three times a day for three cluding analgesic/anti-inflammatory drugs. cific analgesics are generally experienced in days ($14.69 versus $1.09). Drug interactions of concern in den- their use and regard them as effective and Acetaminophen-opioid combinations tistry are listed for the NSAIDs and acet- well-tolerated. are the drugs of choice for moderate to aminophen and for the opioid-like drugs in The NSAIDs listed in Table 3 are the severe pain when NSAIDs are contraindi- Tables 1 and 2, respectively. drugs of first choice for controlling moder- cated. The formulations listed in Table 3 ate to severe pain in dentistry. This degree ensure that the acetaminophen, which pro- Analgesic Selection of pain is characteristically caused by acute vides most of the pain relief, is taken in a The selection of an analgesic for the pulpitis or the surgical removal of impacted dose of at least 600 mg and that the opioid management of acute dental pain is ideally third molars. In doses that produce ceil- is used in a dose (codeine 60 mg, hydroco- based on the pain’s actual or expected ing analgesia, these NSAIDs are better- done 7.5 to 10 mg, oxycodone 7.5 to 10 mg) intensity, the patient’s medical history, the tolerated and at least as effective as the that significantly and consistently increas- drug’s pharmacologic profile, and the ease more traditional acetaminophen-opioid es pain relief in the oral surgery pain model and cost of obtaining the medication. Table combinations. Ibuprofen is unusual in that without usually producing intolerable side 3 lists the authors’ recommendations for the over-the-counter unit dose of 200 mg effects. Hydrocodone as formulated in the typical healthy adult. can easily be used to duplicate prescription Lortab 5/500 or Vicodin (two tablets each, Pain of mild to moderate intensity, as doses (400, 600, 800 mg) of ibuprofen that Table 3) is arguably the preferred opioid, may follow extensive restorative dentistry produce ceiling analgesic effects. While since codeine may be less effective in or simple periodontal surgery, is best man- the COX-2 inhibitor rofecoxib exhibits an certain patients and oxycodone combined aged with analgesics listed in Table 3 that extended duration of action compared to with acetaminophen is a Schedule II drug are usually found in the home. These drugs, other NSAIDs, the authors found the cost requiring a triplicate prescription form. including acetaminophen and ibuprofen, of a prescription for 50 mg of rofecoxib, ev- Opioids -- generally combined with ac-

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etaminophen for prescribing convenience opioid combination currently available, is who are truly allergic to morphine-like opi- -- may also be used as a supplement to an not recommended for routine use because oids. Acetaminophen-tramadol may be the NSAID for additional pain relief if needed the standard dosing schedule of one tablet, preferred choice based on recent efficacy (for example, if the analgesic effectiveness containing 200 mg of ibuprofen and 7.5 mg studies in the oral surgery model.29 of the NSAID is shorter in duration than of hydrocodone, does not provide a ceiling On rare occasion, severe dental pain is the dosing interval). Here, a formulation analgesic effect for the ibuprofen. not satisfactorily relieved with standard such as Lortab 10/650 or Vicodin HP re- Several combinations (acetaminophen analgesic doses. Table 3 lists two regimens duces the acetaminophen dose somewhat. with either pentazocine, propoxyphene, or in which maximum tolerated doses of an Ibuprofen-hydrocodone, the only NSAID- tramadol) are listed in Table 3 for patients NSAID and an opioid are combined that

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1999, pp 247-58. may provide some additional analgesia influence the use of analgesics in dentistry. 3. Chandrasekharan NV, Dai H, et al, COX-3, a cyclooxygenase-1 beyond the drugs already mentioned. Pediatric patients rarely require analgesics variant inhibited by acetaminophen and other analgesic/ The first example combines 800 mg of beyond those obtainable without a pre- antipyretic drugs: cloning, structure, and expression. Proc Natl Acad Sci USA, 99:13926-31, 2002. ibuprofen with 15 mg of hydrocodone, a scription. Ibuprofen oral suspension (100 4. Botting RM, Mechanism of action of acetaminophen: Is dose greater than generally recommended mg/5 mL) at a dose of 10 mg/kg every four there a cyclooxygenase 3? Clin Infect Dis 31:S202-10, 2000. but nevertheless tolerable in the majority hours (to a maximum of 40 mg/kg/day) 5. Stein C, Peripheral mechanisms of opioid analgesia. Anesth Analg 76:182-91, 1993. of nonambulatory patients. The second probably is the most effective oral anal- 6. Desjardins PJ, Cooper SA, Peripherally acting analgesics example involves diflunisal and metha- gesic for children; if acetaminophen with and antipyretics. In Yagiela JA, Neidle EA, Dowd FJ, eds, done. This approach requires a triplicate codeine oral suspension or solution (125 Pharmacology and Therapeutics for Dentistry, 4th ed. Mosby, St. Louis, 1998. prescription for the methadone but may mg acetaminophen and 12 mg codeine/5 7. Cooper SA, Engel J, et al, Analgesic efficacy of an ibuprofen- be superior in patients with inherited or ac- mL) is prescribed, the dose for children 3 codeine combination. Pharmacotherapy 2:162-7, 1982. quired CYP2D6 deficiency. Either of these to 7 years old is 5 mL (1 teaspoon) every six 8. Hersh EV, Moore PA, Ross GL, Over-the-counter analgesics and antipyretics: a critical assessment. Clin Ther 22:500-48, combinations should be prescribed only for hours and twice that for children 7 to 12. 2000. a healthy adult patient whose refractory For elderly patients, regular doses of anal- 9. McQuay HJ, Moore RA, An Evidence-Based Resource for pain is sufficient to require home rest. gesics listed in Table 3 should be reduced by Pain Relief. Oxford University Press, New York, 1998, pp 78-83. 10. Laska EM, Sunshine A, et al, The correlation between 50 percent. Dosage reduction is especially blood levels of ibuprofen and clinical analgesic response. Clin Analgesic Use important for opioid-containing products Pharmacol Ther 40:1-7, 1986. When prescribing an analgesic for den- because of the marked increase in opioid 11. Kiersch TA, Halladay SC, Koschik M, A double-blind, randomized study of naproxen sodium, ibuprofen, and placebo tistry, the dentist should direct the patient sensitivity that accompanies advanced age. in postoperative dental pain. Clin Ther 15:845-54, 1993. to take the initial dose as soon as feasible 12. Fricke JR, Halladay SC, Francisco CA, Efficacy and safety of and then follow a fixed dosing schedule for Conclusion naproxen sodium and ibuprofen for pain relief after oral surgery. Curr Ther Res 54:619-27, 1993. at least the expected duration of the most Returning to the prescription at the 13. Dionne RA, Berthold C, Cooper SA, Therapeutic uses of intense pain (i.e., for two days after surgical beginning of this paper, three errors that non-opioid analgesics. In Dionne RA, Phero JC, Becker DE, eds, tooth extractions). This practice ensures compromise effective pain relief are readily Management of Pain & Anxiety in the Dental Office. Saunders, Philadelphia, 2002. the maintenance of effective drug concen- identifiable: 14. Daniels SE, Desjardins PJ, et al, The analgesic efficacy of trations at the sites of action. Prescribing * Tylenol with codeine #3 contains 300 valdecoxib vs. oxycodone/acetaminophen after oral surgery. J drugs on a “prn” (pro re nata, Latin for “as mg acetaminophen and 30 mg of codeine. Am Dent Assoc 133:611-21, 2002. 15. Malmstrom K, Daniels S, et al, Comparison of rofecoxib and needed”) basis only helps ensure that pain It is not a preferred drug for a patient who celecoxib, two cyclooxygenase-2 inhibitors, in postoperative will be felt. Particularly with NSAIDs, an- can receive NSAIDs. dental pain: a randomized, placebo- and active-comparator- algesics should be ingested before the pain * Giving the patient the option of tak- controlled clinical trial. Clin Ther 21:1653-63, 1999. 16. Morrison BW, Christensen S, et al, Analgesic efficacy of the becomes significant. It takes about two ing one tablet may well result in analgesia cyclooxygenase-2-specific inhibitor rofecoxib in post-dental hours after tissue injury for the induction inferior to that produced by a standard surgery pain: a randomized, controlled trial. Clin Ther 21:943-53, of COX-2 and formation of pro-inflam- dose of acetaminophen alone. The clinician 1999. 17. Stein C, Machelska H, Schäfer M, Peripheral analgesic and matory prostaglandins.30,31 Therefore, should determine the amount of analgesic anti-inflammatory effects of opioids. Z Rheumatol 60:416-24, administration of an NSAID within two to be used, not the patient. 2001. hours of tissue injury will be effective in * The use of “prn” dosing helps ensure 18. McCarthy L, Wetzel M, et al, Opioids, opioid receptors, and the immune response. Drug Alcohol Depend 62:111-23, 2001. preventing postoperative discomfort. the patient will experience postoperative 19. Haas DA, Opioid analgesics and antagonists. In Dionne RA, Because most NSAIDs inhibit both pain before attempting to treat it. Patient Phero JC, Becker DE, eds, Management of Pain & Anxiety in the COX-1 and COX-2 nonselectively, their ad- comfort is improved if analgesics are Dental Office. Saunders, Philadelphia, 2002. 20. Moore PA, Pain management in dental practice: tramadol vs. ministration before hemostasis is achieved taken on a fixed schedule for the first few codeine combinations. J Am Dent Assoc 130:1075-9, 1999. may promote postoperative bleeding. A sig- days. Thereafter, the patient may reduce 21. Raffa RB, Pharmacology of oral combination analgesics: nificant advantage of rofecoxib and other intake in response to the waning noxious rational therapy for pain. J Clin Pharm Ther 26:257-64, 2001. 22. Hyllested M, Jones S, et al, Comparative effect of selective COX-2 inhibitors is that they may stimulus. Thus, a prescription for moder- paracetamol, NSAIDs or their combination in postoperative be given preoperatively for “pre-emptive ate to severe pain in dentistry that meets pain management: a qualitative review. Br J Anaesth 88:199-214, analgesia” without the worry of decreased current knowledge might read as shown in 2002. 23. Breivik EK, Barkvoll P, Skovlund E, Combining diclofenac with platelet function. For surgical cases of ex- Figure 3. acetaminophen or acetaminophen-codeine after oral surgery: tended duration, a single dose of rofecoxib a randomized, double-blind single-dose study. Clin Pharmacol may be beneficial in tiding the patient over References Ther 66:625-35, 1999. 1. Pain terms: a list with definitions and notes on usage. 24. Matthews RW, Scully CM, Levers BGH, The efficacy of until the prescribed analgesics can be taken Recommended by the IASP Subcommittee on Taxonomy. Pain diclofenac sodium (Voltarol) with and without paracetamol in postoperatively. 6:249-52, 1979. the control of post-surgical dental pain. Br Dent J 157:357-9, Age and body size can significantly 2. Stoelting RK, Pharmacology & Physiology in Anesthetic 1984. Practice, 3rd ed. Lippincott Williams & Wilkins, Philadelphia, 25. Forbes JA, Beaver WT, et al, Effect of caffeine on ibuprofen

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analgesia in postoperative oral surgery pain. Clin Pharmacol Ther 49:674-84, 1991. 26. McQuay HJ, Angell K, et al, Ibuprofen compared with ibuprofen plus caffeine after third molar surgery. Pain 66:247-51, 1996. 27. Litalien C, Jacqz-Aigrain E, Risks and benefits of nonsteroidal anti-inflammatory drugs in children: a comparison with paracetamol. Paediatr Drugs 3:817-58, 2001. 28. Robins LN, Helzer JE, et al, Lifetime prevalence of specific psychiatric disorders in three sites. Arch Gen Psychiatry 41:949- 58, 1984. 29. Fricke JR Jr, Karim R, et al, A double-blind, single- dose comparison of the analgesic efficacy of tramadol/ acetaminophen combination tablets, hydrocodone/ acetaminophen combination tablets, and placebo after oral surgery. Clin Ther 24:953-68, 2002. 30. Dionne R, Pre-emptive vs preventive analgesia: Which approach improves clinical outcomes? Compend Contin Educ Dent 21:48, 51-4, 56, 2000. 31. Dionne RA, Khan AA, Gordon SM, Analgesia and COX-2 inhibition. Clin Exp Rheumatol 19(Suppl 25): S63-70, 2001. For a printed copy of this article, please contact/John A. Yagiela, DDS, PhD, UCLA School of Dentistry, 10833 Le Conte Ave., Los Angeles, CA 90095-1668 or [email protected].

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Current Concepts in Pain Management

Steven B. Graff-Radford, DDS

abstract The majority of people afflicted with orofacial pain have acute pain that resolves quickly, but some are left with chronic and disabling pain. Therapy must be provided to deal with the nociception, behavior, and suffering. Appropriate behavioral evaluation may be required prior to developing a treatment plan. The treatment should then be carefully outlined and presented in a treatment-planning visit and may include physical, pharmacologic, and behavioral aspects.

authors

Steven B. Graff- rofacial pain is the result ence.2 The International Association for Radford, DDS, is of a complex interaction of the Study of Pain3 and the International co-director of the Pain Center and an adjunct nociception, pain, suffering, Headache Society4 take the position that associate professor and behavior that afflicts mil- there are better terms for facial pain at UCLA School of lions. The majority of people diagnoses than atypical or idiopathic. Dentistry. O afflicted with orofacial pain have acute The term “idiopathic facial pain” has pain that resolves quickly, but some are included diagnoses such as atypical facial left with chronic and disabling pain. Too pain, atypical odontalgia, masticatory often, this chronic pain is left undiag- muscle disorders, and traumatic neural- nosed; and patients continue to suffer. gia. These categories serve to perpetuate Because dental schools teach little about the limited knowledge of orofacial pain chronic pain, a diagnosis is infrequently where the etiology is unclear. The most made; or patients with non-odontogenic comprehensive facial pain classification pain -- e.g., migraine, cluster headache, to date incorporates the International trigeminal neuralgia, or myofascial pain Headache Society criteria and expands -- are misdiagnosed. The term “atypical” it to include disorders that were not is often suggested to categorize the pain clearly defined.4 It is suggested that and implies a psychiatric or behavioral if the clinician does not know what is problem.1 “Idiopathic,” when referring causing the pain, the term “idiopathic” to a medical problem, suggests there is or “pain of unknown origin” be used. The something unknown and does not define patient should then be referred for better the problem. The same applies to terms diagnosis. The major categories of pain are incorporating the word “atypical.” It has intracranial, extracranial, musculoskeletal, been reported that patients described as neurovascular, neuropathic, and psycho- atypical or idiopathic can be diagnosed if genic. In many categories, the etiologic evaluated by someone with more experi- mechanism, peripheral and/or central, is

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poorly understood. Pain disorders must she should consider referring the patient. to alternative plans if the first choice be classified based on an understanding of The dentist must try to understand each is not working out. Once a treatment the underlying mechanism, etiology, and component of the chronic condition so program is established, the treatment clinical presentation. It is also necessary a comprehensive and structured therapy contract will help ensure compliance. Ad- to recognize the differences in acute and can be offered. Therapy must be provided ditionally, if the patient and clinician sign chronic pain because treatment approach- to deal with the nociception, behavior, the treatment contract, the full course of es are different.5 and suffering. Appropriate behavioral treatment is agreed upon, preventing the Acute pain may best be described as a evaluation may be required prior to de- patient from dictating changes. useful pain, e.g., acute pulpitis, mucosal veloping a treatment plan. The treatment Setting goals is important in a treat- irritation secondary to a prosthesis, and should then be carefully outlined and ment contract. It is recommended that active infection. It is the essential com- presented in a treatment-planning visit. the treatment goals be stated as behaviors ponent that allows the sufferer and his Treatment may include physical, pharma- (process goals) to be learned, increased, or her practitioner to know something is cologic, and behavioral aspects. Using a decreased, or eliminated, rather than spe- wrong. It usually lasts a predictable time. structured treatment agreement is helpful cific percentage reductions in pain (end If the duration extends beyond what is in explaining therapy to patients. goals). The goals need to be realistic and expected, further investigation is needed; attainable. or a chronic etiology may be expected. Treatment Planning Setting treatment duration is useful There is little difficulty in defining the A treatment contract is a written in allowing specific therapies to be tested specific pathology (e.g., denture irrita- agreement between a patient and health prior to re-evaluating and moving forward tion) of acute pain; and therapy is usually care provider.6 This is imperative in a set- with alternatives or proceeding with obvious (e.g., removal of irritating source). ting such as a chronic pain center where further workup. The treatment contract Chronic pain typically begins with an patients receive simultaneous treatment should specify therapy duration and fre- acute episode and progresses to a chronic from multiple specialists. In clinical prac- quency. In patients for whom noncompli- condition if it is inappropriately managed, tice, using this concept helps to prevent ance or tardiness is a possibility, conse- no treatment is sought, or treatment was patients who are not responding from quences may include stopping therapy or not completed, e.g., a peripheral neuro- being overtreated. Patients who suffer referring the patient for inpatient care. pathic pain may develop following a her- from chronic disease often feel a loss of By agreeing to a treatment contract that pes infection that causes acute pain. The self-control. Too often, they have been sets a time limit, the patient is made pain duration is usually defined as being given the false promise that the next sur- aware that there is a treatment constraint. longer than six months. The pain is not gery, medication, or alternative therapy Therefore, there is a consequence if he or necessarily useful and is frequently associ- will “cure” the problem, only to be disap- she misses appointments or does not fol- ated with increased anxiety and depres- pointed. It is therefore recommended that low the instructions outlined. sion, possibly because numerous doctors a treatment contract be used to provide Sharing responsibility for treat- have been seen and numerous procedures clear treatment explanations, set treat- ment outcome is especially important in tried without mitigation of the pain. ment goals, set treatment duration, define chronic pain patients. It is not uncom- the patient’s and health care providers’ mon for the patients’ expectation to be Management Approaches for Chronic responsibilities, and provide specific con- unrealistic. In chronic migraine, it is not Pain tingencies to enhance compliance. possible to “cure” the pain. Migraine is a A practitioner must carefully assess When providing a treatment explana- genetic disorder that at this time can only and diagnose the pain before developing tion, it is suggested that all treatment be managed. Therefore, a treatment con- a therapy. Treatment should be aimed at a possibilities be discussed. Where possible, tract will define what the patient needs specific diagnosis or pain mechanism. Us- this should be provided in stages, espe- to do to manage the pain as opposed to ing poorly defined diagnoses such as atyp- cially if one component of therapy is con- what the clinician can do for the patient. ical trigeminal neuralgia or atypical facial tingent upon the success of another. It is Pain management usually requires a pain should be avoided. If a practitioner recommended that all possible therapies multidisciplinary approach. Patients who cannot make an accurate diagnosis, he or be outlined, allowing flexibility to change are exposed to more than one clinician

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are apt to receive conflicting information ing a neutral spine position. Sitting with massage, moist heat, ultrasound, elec- or may conveniently interpret informa- appropriate lumbar support and taking trical stimulation, or other distraction tion as conflicting to split the team. The regular breaks from sitting hunched over techniques.8,10-12 Applying a distraction treatment contract enables one person, a workstation are recommended. Good stimulus (cold in fluoromethane spray and “the pain manager,” to coordinate the head position requires keeping the ear stretch) allows the muscle to be exercised treatment team. All questions or prob- aligned over the shoulder and hip while without restriction. This normal function lems should be discussed with the pain sitting and standing. Appropriately may be the necessary input to trigger cen- manager. The entire team, including the modifying the workstation and ensur- tral nervous system inhibition. Botulinum referring physician and pharmacy, should ing eyewear is well-adjusted will prevent toxin has been described for muscle pain have a copy of the treatment contract to anterior head position (jutting the head and headache.13 Its function is likely inde- prevent miscommunication. forward) and eyestrain. Jaw position is pendent of the muscle paralysis it creates, The treatment contract can be used to also significantly affected by anterior instead it may exert its effect by reducing define contingencies. Behaviors that are head positioning.8 Patients should also be peripheral neural sensitization.14 Acu- required and prohibited should be speci- informed to keep the tongue touching the puncture points often coincide with the fied. These may include issues related to palate with their teeth unclenched. In cer- trigger points, and needling these points missed appointments, late arrival, medi- tain situations, if cervical spine range of may in part affect pain through peripheral cation usage (decreasing dose schedule, motion needs correction, physical therapy and central processes. Acupuncture may time contingent administration vs. pain involving cervical mobilization techniques not be more effective than placebo or contingent administration), noncompli- may be used. These techniques, whether massage.15,16 ance, and home program. The conse- direct (manual) or indirect (through quences of undesirable behaviors should specific therapeutic exercises), address Nerve block be clearly spelled out. dysfunctions found in the cervical spine.9 Neural blockade is useful in neuro- Treatment is aimed at restoring normal pathic pain conditions. Neuropathic pain Therapies joint relationships and range of motion as by definition requires there to be damage Orofacial pain may be addressed with well as restoring muscles to their origi- to the peripheral or central nervous sys- a variety of physical, pharmacologic, and nal resting length. Traction, moist heat, tem to activate the pain mechanisms.17 behavioral strategies. Therapy principles ultrasound, and massage are used only as The injury may be obvious, such as that and rationales will be discussed, rather needed to facilitate the mobilization. following nerve severance or stroke, or than disease-specific therapies. minor, such as that as following bruis- Trigger-Point Therapy ing, infection, or compression. Broadly Physical Trigger-point injections serve as a neuropathic pain is defined as sympa- diagnostic and therapeutic technique. thetically maintained and sympathetically Exercise In myofascial pain, injecting local anes- independent pain.18 Neural blockade is Posture and body mechanics as they thetic (usually 1 percent procaine) into the effective in differentiating sympatheti- relate to working and relaxation should be tender or active trigger point will decrease cally maintained pain (complex regional considered in musculoskeletal pain and the pain temporarily.7,8 It is believed this pain syndrome) from sympathetically neurovascular disorders.7 Poor posture is should be done to relieve the pain so that independent pain. It may also be effective thought to affect most people, but when the patient may function normally for in controlling sympathetically maintained there is nociceptive activity in a muscle, some time, thereby allowing central inhi- pain if used repetitively. Stellate ganglion further nociceptive input, caused by poor bition to activate. Doing the trigger point blocks, phentolamine infusion,19 and posture, might trigger a greater pain re- injections without addressing perpetu- sphenopalatine blocks have been de- sponse. It has been proposed that posture ating factors and providing an exercise scribed as useful in obtaining a chemical related to sitting, standing, and sleeping program has limited value.10 sympathetic block. Somatic block may be discussed with the chronic head and There are other means whereby the help identify the pain source. Rarely neck pain sufferer. Patients are trained trigger point may be converted from is this effective as an isolated therapy. to sleep on their back or side, emphasiz- active to latent, using spray and stretch, Steroid combinations may provide pro-

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longed relief, but care should be exercised may prove useful. Topical anesthetics on ment, is not well-studied.24 It does not because local submucosal steroid use may their own are effective in acute pain states seem that occlusion is a major factor in result in tissue sloughing or if the steroid and have limited use in chronic pain. TMD, and significant alterations in occlu- is injected into the face, the resultant fat Lidocaine patches are beneficial if the sion as a first line of therapy should be necrosis may produce dimpling. Lidocaine pain is extraoral, but continuous intraoral avoided. infusion (200 mg over one hour) may be delivery is a challenge. Using a neurosen- used therapeutically in various forms of sory shield may allow longer applications Surgery neuropathic pain.20 It is suggested that intraorally.21 The dentist may manufac- Although not suggested as a therapeu- response to intravenous lidocaine may ture a custom acrylic stent to fit over the tic modality for trigeminal neuropathic predict who responds to the lidocaine ana- pain site. This is held in place, and the pain, surgery is an excellent alternative logue mexiletine. topical agent is repeatedly applied to the for trigeminal neuralgia. The most effec- Spinal blocks, including selective gingival surface. Clonidine can be applied tive surgical approach remains micro- nerve root block and epidural and facet to the hyperalgesic region by placing the vascular decompression.25 Advances in injections are useful if there is a local proprietary subcutaneous delivery patch microvascular decompression include the nociceptive source driving the pain. Often where it is most tender. Alternatively, the use of an endoscope. This allows clearer magnetic resonance or other imaging use of a 4 percent gel can be compounded observation and is less traumatic.26 points to the nociceptive source. This and delivered over a larger area. Topical Gamma knife radiosurgery is a recent may then be addressed using fluoroscopic clonazepam (0.5 to 1.0 mg three times per advance for trigeminal neuralgia.27 This guided procedures. Placing a steroid at day) has been effective at reducing a burn- technique offers a relatively non-invasive the source may help reduce the inflamma- ing oral pain.22 Patients were instructed means for lesioning the trigeminal nerve tory driver and allow physical therapy and to suck a tablet for three minutes (and adjacent to the pons using a 4 mm col- exercises to restore function. then spit it out) three times per day for limator helmet. Complications are rare, Neural blockade with medications at least 10 days. Serum concentrations and to date the author has seen one case other than local anesthetics and steroids were minimal (3.3 ng/ml) one and three of trigeminal dysesthesia attributed to has been described for facial pain. Neural hours after application. Woda hypoth- the procedure. There are numerous other destruction may be intentionally created esized there was a peripheral not central surgeries that may be useful in orofacial with alcohol or glycerol. Creating anes- action at disrupting the neuropathologic pain. Use of surgery for TMD depends thesia dolorosa or deafferentation pain mechanism. One may consider using upon the etiology. Arthrotomy and open should be considered prior. Studies with other topical agents such as ketamine, joint surgery are far less necessary since streptomycin applied to patients with tri- carbamazepine, amitriptyline, nonsteroi- the improved use of arthrocentesis and geminal neuralgia have not been effective dal anti-inflammatories, and steroids; but arthroscopy.28 Future surgical care may in placebo-controlled trials. their benefits have not been systemati- include neural stimulation. Currently this cally studied. is experimental. Topical Therapy The use of topical therapies has not Splint -- Intraoral Orthotic Device Pharmacologic been well-studied. There is some evidence There are numerous splint designs Pharmacologic intervention for chron- that capsaicin applied regularly will result and as many theories as to how and why ic orofacial pain is sometimes essential to in desensitization and relief in neuro- they work for pain. The exact mechanism allow central nervous system inhibition pathic pain. This may deplete substance whereby patients are helped by splints is and facilitate the peripheral therapies. P and thereby desensitize the pain site. elusive. It is recommended that the sta- It is essential that the dentist treating The recommended dose is five times per bilization appliance be used because the chronic pain understands that the medica- day for five days and then three times per relative risk is minimal.23 Splint therapy tions used to alter pain in the trigeminal day for three weeks. If the patient cannot still remains the indicated therapy for nerve distribution may act centrally or withstand the burning produced by the temporomandibular disorders and muscle directly on the nerve to reduce the pain application, the addition of topical local pain. Its use for migraines, where there is and suffering. Often, the medications fall anesthetic, such as 4 percent lidocaine gel, no temporomandibular or muscle involve- into categories such at antihypertensives

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(beta blockers, calcium channel blockers, most appropriate interventions. Consid- inhibition (e.g., medication and/or behav- alpha adrenergic agents), antidepres- eration should be given to the following ioral intervention) may reduce the pain, sants (tricyclic antidepressants, selective factors: behavior changes, and suffering. serotonin reuptake inhibitors, mono- * Behavioral or operant; Current advances in knowledge amine oxidase inhibitors), antiepileptic * Emotional; regarding pain mechanisms have made drugs (membrane stabilizers, GABAergic * Characterlogical; therapy for chronic pain patients more drugs), or specific receptor agonists that * Cognitive; successful. Patients should be afforded are not Food and Drug Administration- * Side effects; therapy from as broad and all-encompass- approved for pain but are commonly used * Medication use; and ing a base as possible. “off label.” Certainly, the classes specifi- * Compliance. cally approved for pain conditions such To reduce behavioral stressors, stress Table 1. Medications Used in as anti-inflammatories, muscle relaxants, management and relaxation skills are Orofacial Pain narcotic and non-narcotic analgesics, trip- used. Cognitive behavioral training Analgesics tans, and ergots are also commonly used provides skills for coping with daily life for the chronic orofacial pain patient. stresses, depression, and pain.29,30 In Narcotic For chronic benign pain, the goal addition, patients are presented with Non-narcotic should be to limit narcotic use. In certain information regarding myofascial pain Antidepressants circumstances, there are no alternatives; and operant aspects of pain and medica- and carefully controlled use is necessary. tion use. Tricyclic antidepressants It is recommended that patients under- Selective serotonin reuptake inhibitors stand the therapeutic goal is to keep them Conclusion Monoamine oxidase inhibitors functional. If they maintain the agreed Because pain comprises nociception, behavioral function, continued narcotic behavior, and suffering, careful attention Antiepileptic drugs use should be provided. If these behaviors to creating a comprehensive therapy is Membrane stabilizers are not met, withdrawal from this treat- essential. The clinician should not revert GABAergic agents ment may be needed. It may be useful to a psychogenic etiology as a default, to have this withdrawal performed by a rather, understanding that all pain, no Antihypertensives detoxification specialist. If medication is matter what the etiology, has a behavioral Alpha blockers to be withdrawn, a protocol for this must component will allow the patient the Beta blockers be outlined. At times, a blinded process is opportunity to receive behavioral therapy used to help reduce anxiety over stopping alongside antinociceptive modalities. Calcium channel blockers the narcotic. Consent is obtained when The current understanding that pain Muscle relaxants using the blinded pain cocktail. The medi- may be generated from peripheral and Serotonin antagonists cation is reduced usually by 20 percent central mechanisms further warrants per week. Care should be provided to deal the therapy to be aimed not only at the Serotonin agonists with withdrawal symptoms. peripheral source, but also at the brain Ergots (nonselective) Table 1 summarizes the common pain inhibition systems. A patient who Triptans medication classes used in orofacial pain. has a toothache after an extraction or root This is not an exhaustive list, and dentists canal therapy may not have a peripheral References treating orofacial pain may use other source for the pain, rather the pain may 1. Graff Radford SB, Solberg WK, Atypical odontalgia. J Cal groups not listed. be generated by an ongoing process in Dent Assoc 14(12):27 32, 1986. the trigeminal nucleus or elsewhere in 2. Fricton JR, Critical Commentary. A unified concept of idiopathic orofacial pain: Clinical Features. J Orofacial Pain Behavioral the brain. Treatment aimed solely at the 13(3):185-9, 1999. Following a behavioral evaluation, tooth site may only worsen the situation, 3. Mersky H, ed, Classification of chronic pain: description of management is directed at the factors that whereas treatment aimed at stabilizing chronic pain syndromes and definition of terms. Pain, suppl. 3:S1, 1986. may affect treatment and determining the neural excitability or enhancing central 4. Headache Classification Committee of the International

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Headache Society, Classification and diagnostic criteria 20. Sinnott CJ, Garfield JM, Strichartz GR, Differential efficacy for headache disorders, cranial neuralgias, and facial pain. of intravenous lidocaine in alleviating ipsilateral versus Cephalalgia 8:1-96, 1998. contralateral neuropathic pain in the rat. Pain 80:521-31, 1999. 5. Graff-Radford SB, Disorders of the mouth and teeth. In, 21. Graff-Radford SB, Facial pain of undetermined origin. In, Silberstein SD, Lipton RB, Dalessio DJ, eds, Wolff’s Headache Rappaport A, Sheftell F, Purdy A, eds, Advanced Therapy of and Other Head Pain, 7th ed. Oxford Press, Chicago, Vol 7 2001, Headache: Case Based Strategies for Management. BC Decker pp 475-93. Publishers, Hamilton, Ontario, 1999, pp 263-9. 6. Graff-Radford SB, Treatment contracting for chronic pain 22. Woda A, Navez M-L, et al, A possible therapeutic solution patients. Los Angeles Psychologist 13(1):9, 26, 1999. for stomatodynia (burning mouth syndrome). J Orofacial Pain 7. Graff-Radford SB, Regional myofascial pain syndromes and 12:272-8, 1998. headache, principals of diagnosis and management. Current 23. Solberg WK, Temporomandibular disorders: Masticatory Pain Headache Reports 5:376-81, 2001 myalgia and its management. Br Dent J 160:379-85, 1986. 8. Travell JG. and Simons DG, Myofascial Pain and Dysfunction: 24. Graff-Radford SB, Forssell H, Oromandibular Treatment. In, The Trigger Point Manual. Williams and Wilkins Co, Baltimore, Olesen J, Tfelt-Hansen P, Welch KMA, eds, Headaches. Raven 1988. Press, New York, 2000 pp 657-60. 9. Maitland GD, Vertebral Manipulation, 4th ed. Butterworths, 25. Janetta PJ, Trigeminal neuralgia: treatment by London, 1977. microvascular decompression. In, Wilkins RH, Ragachary SS, 10. Graff Radford SB, Reeves JL, Jaeger B, Management of eds, Neurosurgery. McGraw Hill, New York, 1996, pp 3961-8. headache: the effectiveness of altering factors perpetuating 26. Jarrahy R, Berci G, Shahinian HK, Endoscope-assisted myofascial pain. Headache 27:186 90, 1987. microvascular decompression of the trigeminal nerve. 11. Mennell JM, Spray-stretch for relief of pain from muscle Otolaryngol Head Neck Surg 123(3):218-23, 2000. spasm and myofascial trigger points. J Am Pod Assoc 66:873- 27. Young RF, Vermeulen SS, et al, Gamma knife radiosurgery 6, 1976. for treatment of trigeminal neuralgia. Idiopathic and tumor 12. Jaeger B, Myofascial referred pain patterns: the role of related. Neurology 48:608-14, 1997. trigger points. J Cal Dent Assoc 13(3):27-32, 1985. 28. Montgomery MT, Van Sickels JE, et al, Arthroscopic TMJ 13. Freund B, Schwartz M, Symington JM, The use of botulinum surgery: Effects on signs, symptoms, and disc position. J Oral toxin in temporomandibular disorders: preliminary findings. J Maxillofac Surg 47:1263-71, 1989. Oral Maxillofac Surg 57:916-20, 1999. 29. Reeves JL, EMG-biofeedback reduction of tension 14. Royal MA, The use of botulinum toxins in the management headaches: a cognitive skills training approach. Biofeedback of pain and headache. Pain Practice 1:215-35, 2001. Self Regulation 1:217-25, 1976. 15. Tavola T, Gala C, et al, Traditional Chinese acupuncture in 30. Holroyd KA, Andresik F, Westbrook T, Cognitive control tension type headache a controlled study. Pain 48:325-9, 1992. of tension headaches: a cognitive skills training approach. 16. Ahonen E, Mahlmaki S, et al, Effectiveness of acupuncture Cognitive Therapy and Research 1:121-33, 1977. and physiotherapy on myogenic headache. A comparative To request a printed copy of this article, please contact/ study. Acupunct Electrother Res 9:141-50, 1984. Steven B. Graff-Radford, DDS, 444 S. San Vicente, #1101, Los 17. Campbell JN, Raja SN, Meyer RA, Painful sequellae of Angeles, CA 90048 or at [email protected]. nerve injury. In, Dubner R, Gebhart GF, Bond MR, eds, Pain Research and Clinical Management. Elsevier, Amsterdam, the Netherlands, 1998. 18. Graff-Radford SB, Facial pain. Curr Opinion Neurolog 13:291-6, 2000. 19. Scrivani SJ, Chaudry A, et al, Chronic neurogenic facial pain: Lack of response to intravenous phentolamine. J Orofacial Pain 13:89-96, 1999.

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Pitfalls of Being a Patient Record Pack Rat

There are many reasons to look about thinning the herd, so to speak, it has also our office with pride. Our collection of produced an inactive file approximately used diamonds, for example, is second to 100 times the size of the active file, and none. The 3M Company has recognized that’s why we can’t get the car in the us as being the most innovative users of garage anymore. yellow Post-It notes in the Dental Offices Even more depressing is the discovery Under 1,000 Square Feet Division. The that we are facing what appears to be Southern California Edison Company has thousands of individuals who, because often publicly marveled at the number of they have not been in for 10 years or extension cords we have emanating from more, force us to ask ourselves “Why?” Robert E. a single power outlet. What immediately comes to mind, of Horseman, DDS Yet, there is one area that threatens to course, is the distinct possibility that the erase the smugness of these accomplish- work we did for them was so good they ments. It is the disposition of patient will never require any more dentistry. records. Our custom over the years has We concede that some may have been to simply decamp from our venue moved out of the area or to that ultimate when patient records reached the point “beyond,” but what about those who where they occupied 68 percent of the didn’t return because we hurt them, we total office space, leaving the next tenant didn’t live up to their expectations, we the task of disposal. Nomadic tribes used were too expensive or, worse yet, too to do this when their accumulated refuse cheap? Were we too old, too hairy, too gave even the most tolerant of them pushy, too wishy-washy, too fat, too ema- migraines. The heady feeling of the chance ciated or so totally lacking in charm and to start over with a clean slate is admit- ordinary social graces that wild ponies tedly attractive but can interfere with the couldn’t drag them back? continuity of treatment. This does not Write this legibly on a yellow Post-It mean you shouldn’t move just beyond the and stick it on your forehead: DON’T GO limit that lower denture patients are will- THERE! Analysis of one’s shortcomings ing travel to seek you out. is an exercise best left to one’s spouse. So we came up with Plan B: a simple Instead, work on getting your active files, solution, really, involving the removal now purged of all these missing hordes, from our files of all the patients who into some sort of recognizable alphabeti- had not visited during the past 10 years. cal order. “Alphabetical” is the keyword Although this has the desirable effect of here. Sometimes temporary staff has

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innovated a filing system involving first away. That’s why their cupboards are full instead of last names, or hair color, thus of stuff for which they have no earthly ensuring themselves an indispensable use. If it weren’t for assistants who dar- position as the only employee able to find ingly give the heave-ho to vast quantities anything. of this junk when the doctor is on vaca- You realize that all these missing tion, the whole profession would grind to people were the recipients of your recall a halt for lack of space. We don’t need a cards, the ones with the charming little law to tell us to keep all these records, we first molar brandishing a toothbrush and would just keep them with all the other asking that they call your office RIGHT useless stuff anyway. We can’t help it. But NOW for an appointment because it has really, who cares what we did on Joe Blow been six months since their last visit and 10 years ago? We can’t even read our writ- you are worried sick that their oral health ing. What we want to know is what are we will be endangered if they procrastinate going to do with Joe right NOW. a minute longer. These are the cards that Which brings us to Plan C. All the cost 23 cents apiece to mail and carry the dentists in your town who are speaking same imperative impact that other unso- to one another gather up all their ancient licited junk mail delivers. records and anything else they are willing There is a theory that the surest way to relinquish. We stack all this impedi- to see a long-absent patient suddenly menta in a huge pile after getting the reappear is to place his or her records proper permits from the City Council, the in an inaccessible place, perhaps in an Fire Department, the EPA and the ACLU, incinerator. This is an unreliable ploy at and torch it. best, vying with the recall card in results, The act of culling, of purging, of but cheaper. expunging can be a liberating experience. The law states that patient records Deny yourselves no longer! must be maintained for a minimum of seven years. Why seven instead of five or eight, nobody knows. Why are there seven days in a week, or why can a soft drink with a name like 7 UP be bought at a 7-Eleven? It never came up for a vote. One of the enduring characteristics of dentists is that they never throw anything

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