cda journal, vol 27, nº 2

CDA Journal Volume 27, Number 2 Journal february 1999

departments 94 The Editor/Doing the Right Things 96 Impressions/Children Reap Benefits From One Man’s Desire to Help 162 Dr. Bob/The Emperor’s New Dental Smock

features

117 Current Views on Periodontal Therapy An introduction to the issue. By David F. Levine, DDS

118 Periodontal Regeneration: Myth or Reality Periodontal regenerative procedures are evaluated and their patient benefits determined. By William Becker, DDS, MSD

125 A Review of Osseous Resective Surgery The controversy surrounding the removal or reshaping of supporting bone is discussed. David F. Levine, DDS, and Greg Filippelli, DDS

135 Periodontal Medicine: Assessment of Risk Factors for Disease The link between and systemic health conditions is explored. By Perry R. Klokkevold, DDS, MS

143 Surgery: a Restorative-Driven Periodontal Procedure The proper management of periodontal tissues necessary to help ensure long-term restorative success is discussed. By David F. Levine, DDS; Mark Handelsman, DDS; and Nicolas A. Ravon, DDS

february 1999 3 Editor cda journal, vol 27, nº 2

Doing the Right Things

Jack F. Conley, DDS

he December 1998 “Views” Meskin be possible. column of Journal of the Another one of the “right things” the American Dental Association profession must ultimately come to an Editor Lawrence Meskin agreement on if is to continue brought forth some very to experience the status of income and Tpositive news. Dr. Meskin noted that respect that it has earned, is the concept “After years of flat or even decreasing of continuing competency assessment. take-home income (for dentists), For more than four years, leadership and substantial increases recently have a dedicated committee of the California been noted.” He reported increases of Dental Association have actively debated 31 percent for general practitioners and this issue and its many ramifications. 40.9 percent for specialists since 1986. These deliberations resulted in a voluntary Further, he noted that these increases assessment program (QUIL3) and, most exceed income growth in other health recently, a CDA position paper titled professions, with the average real income “Concepts of Continued Competency,” of dental GPs surpassing that of physician which was approved by the 1998 CDA family practitioners! Meskin’s data also House of Delegates. suggests that the smaller, traditional It is doubtful this position paper will dental office demonstrates economic slow public interests outside of dentistry advantages not seen in the larger and other health professions from seeking multidentist practices. The economies of a active mechanisms to periodically evaluate larger scale operation apparently are more the competency of health care practitioners. difficult to achieve in dentistry than in As an example of efforts on behalf of other fields. the public interest, in November 1998, This positive news will undoubtedly the Pew Health Professions Commission disappoint the gloom and doomsayers we released a proposal that, if carried forward, encounter from time to time who allege would require a written examination and that dentistry has retreated from the require state regulators to conduct in-office position of prestige and income expectation inspection of treatment procedures and it once enjoyed. The point to be made here patient records at least every six years for is that dentistry and many colleagues physicians and “other health workers.” The individually and collectively must be doing chairman of this independent commission, the right things! As examples, we list which has no power beyond persuasion, education of the public (the dental patient) is George Mitchell, a former U.S. Senate about the importance and value of the majority leader. He stated that “Once service dentistry provides, fluoridation, you are in the club, you are in forever. We and the continuing efforts of the organized became convinced there is today, a public profession to support a strong code of system which isn’t protecting the public.” professional ethics and develop appropriate Whether or not the initiatives of standards of care. Without these strengths, “persuasion” from this commission are the private practice of dentistry would successful in achieving the stated goal, this certainly not be sought after by increasing issue will continue to confront the dental numbers of dental school applicants, profession. The position statement recently nor would the statistics discussed by Dr. approved by the CDA House was the latest

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compromise affecting association policy on profession. However, we believe it to be the this controversial issue. It takes a position “right thing” in shaping a successful future that must be more visible than secluded for the dental profession. residence in the CDA Policy Manual! It does acknowledge that activities such as the aforementioned Pew Commission report will be occurring and must be monitored: “Given present trends related to post-licensure competency assessment, the association will best serve its members by closely monitoring regulatory and legislative bodies and managed care organizations which may seek to impose mandatory continued competency.” Many CDA resources were expended in developing standards and methodologies that could serve as a model. While QUIL3 resulted from these efforts, even the recent position statement had to survive numerous revisions over a two-year period before gaining approval. Given the high level of dissatisfaction in dental circles with any discussion of “continuing competency” (yes, some colleagues even sought to adopt alternative terminology to use for “continuing competency,” deeming its very mention unacceptable), the final sentence in the position statement is the most important and far-reaching: “California Dental Association should make every effort possible to have a proactive and participatory role in the process of researching, defining, and developing such programs [continuing competency assessment].” If the good news discussed by JADA Editor Meskin is to be continued into the future, the profession will need to reject the complacent approach of the position paper and instead seek to carry out the proactive intent of its final passage. To date, the proactive approach to this issue has been controversial within the

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Impressions cda journal, vol 27, nº 2

Children Reap Benefits From One Man’s Desire to Help By David G. Jones Perhaps it is fate, destiny putting the right person in the right place at the right time. More likely, it is the result of thorough training, hard work and a passionate approach to providing care for those who seem to need it most. Regardless of the confluence of forces making it a reality, Jerry L. Lanier, DDS, is making a difference in the lives of thousands of children. Through his two clinics in the Los Angeles area and his far-reaching program to provide care for underprivileged children, Lanier is fulfilling his long-held desire to offer the possibility of better oral health to children who otherwise might not have it. Lanier, 43, was one of 11 children born affordable, and I saw kids up and down with school nurses. They are on the front to uneducated parents in a backwoods the streets, so I didn’t need to do any line and see the kids with toothaches and North Carolina town. He attended Me- demographic study. I just looked for the mouths in terrible condition.” harry Dental School in Nashville, Tenn., strollers.” Lanier’s registered dental assistant on a scholarship and originally planned Lanier wanted to give his new clinic developed a skit to present to the school- to specialize in oral surgery following his a catchy name, one that clearly commu- children. Now, according to Lanier, many 1983 graduation. But four years of work- nicated a high level of care and commit- schools are requesting presentations. ing on youngsters at a children’s dental ment to his young patients. “She goes to the school in her RDA clinic changed his mind. “I wanted to give the clinic a name uniform and uses a hand puppet to “While working at a clinic in a New Or- that explained our entire mission,” Lanier demonstrate proper brushing technique leans housing project, I saw so many kids says. “With a three-word name, Kids while singing a song in Spanish to the who needed treatment and couldn’t afford Dental Kare, I wanted people to know we children,” he says. “Sometimes I take my to go elsewhere,” says Lanier, a member of are there to treat kids, and the care we guitar along and play, and the kids love the Los Angeles Dental Society. “I realized provide was something special, just for being involved.” there was a lot of suffering going on, and kids.” After five years of work at the clinic, it made me realize this career was some- Soon after the clinic opened, it was Lanier and his associates have treated thing special.” February, Children’s Dental Health more than 12,000 children. A year ago, After working for the Public Health Month. Lanier decided to make a con- while gearing up for a new office opening, Service in New Orleans, Lanier moved certed effort to establish relations with Lanier wanted to make his young patients to Los Angeles in 1991 and worked in a the mostly Hispanic and Armenian com- feel more at ease. Today, the 40 patients variety of dental offices. Finally, he struck munity surrounding the clinic. he and his associates treat daily have a lot out on his own. “I wanted within the month to go to of entertainment choices. “I was riding around and saw an every school in the area,” Lanier says. “I “The new office has a movie room with abandoned dental office for lease in a gave away in every class- surround sound, a video room with game low-income neighborhood,” Lanier says. room and spent almost every morning stations, and quite a large waiting area “I couldn’t afford a lot, this place was going from one school to the next to meet with lots of play toys,” he said. “We even

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Discipline is the Key to Investment Highs and Lows Following a disciplined approach is one of the first rules of successful investing, particularly with stocks. Two time-tested investment strategies, based on stocks in the Dow have a TV in each of the 17 operatories Jones Industrial Average, have shown that discipline can pay off over time. These strategies with intraoral cameras.” are known as Top 10 and Low Five. Lanier also operates a mobile screening Under the Top 10 strategy, an investor buys the 10 highest-yielding common stocks in van that stops at schools, health fairs, and the Dow Jones and holds them for 12 months. After 12 months, any stocks that are no longer anywhere in the area where there is a group among the Top 10 are sold, and any that are new to the list are bought. of 20 or more children. He and his associ- With the Low Five approach, an investor purchases the five lowest-priced of the 10 ates -- general dentist Michael Rice, DDS; highest-yielding Dow Jones common stocks and holds them for 12 months, after which time and pediatric dentists, Michael Vert, DDS, the investor makes readjustments so that he or she continues to hold the five lowest-priced and Scott Fishman, DDS -- are busy: They of the 10 highest-yielding Dow Jones stocks. do at least 50 screening events a year, for a total of about 10,000 screenings annually. At the screenings, they give away tooth- brushes, balloons and dental education stocks offering moderate dividend yields aged care blues tunes. They’ve recently kits. He accepts no donations from outside may perform better during weak markets recorded the CD single “Mastoid Sally.” sources to support his efforts. than stocks that do not pay dividends. The parody is a follow-up to the band’s For Children’s Dental Health Month 4. The strategies may be carried out CD, “Minimal Service CPT 99211,” which 1999, Lanier plans to participate in four either by individual investors or, for also bemoans the confusion and red tape health fairs with area physicians, the Red sometimes as little as $1,000, through often associated with HMOs. Cross and other agencies, and to visit up professionally selected fixed portfolios of “Mastoid Sally” is a foot-tapping, to two schools a day to do screenings, for securities offered by major financial firms. teeth-grinding tribute to dentists sung to a total of about 50 screenings and presen- (Please note that the Dow Jones the tune of “Mustang Sally.” The band’s tations during the month. Industrial Average and Dow Jones are the keyboard player, Dr. Jimmy Pantel, is a “We’ll also give out up to 50,000 property of Dow Jones & Company, Inc., dentist. toothbrushes and work to educate a lot which is unaffiliated with and has not “We wanted to do a song specifically of parents during that time,” he said. “I participated in any way in the creation of for our colleagues in dentistry and otolar- believe one of the things lacking most in the Top 10 and Low Five strategies or any yngology,” Bierstock says. “Not everyone children’s dentistry is education. Most products based on these.) realizes that dentistry has many concerns of the time parents don’t know anything Marios Gregoriou is associate vice about managed care just as the rest of the about caring for primary teeth, so we president and financial adviser with Mor- health care industry does.” want to give them a little education. Our gan Stanley Dean Witter in Sacramento. With managed care issues dominating focus during the month is to educate He can be reached at (800) 755-8041. headlines and emerging as a top concern parents and raise awareness.” Information in this article was obtained for millions of Americans, Bierstock, a from sources considered to be reliable. former eye surgeon, says he recorded the Here are four reasons that these This article does not constitute invest- song after it was repeatedly requested strategies appeal to investors: ment advice. Consult an investment ad- at performances and on his web site. He 1. The 30 companies in the Dow Jones viser before making investment decisions. says people enjoy the humorous twist to are large, well-known and the “blue chip” the song, which describes Sally’s ongo- names. Singin’ the Managed Care Blues ing battle with bruxism and TMD. In the 2. When buying the highest-yielding Just as managed care has come to song, the dentist admonishes: stocks, investors are in effect purchas- dominate medicine and is making greater Mastoid Sally, guess you better slow ing issues that may be out of favor. The inroads in dentistry, HMOs’ biggest musi- that chewing down. high yield can mean the share prices are cal critic has segued into the dental arena Mastoid Sally, guess you better slow depressed and have potential for apprecia- with his latest tune, “Mastoid Sally.” that chewing down. tion. Dr. Sam Bierstock and his band of You been grinding in your sleep girl. 3. The yields may provide support for “preferred music providers” have added a Guess I better do a bonding or a crown. the stock prices in down markets because dental ditty to their repertoire of man- Bierstock’s satire has not escaped

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Intervention Helps Teen Athletes Quit Spit High school baseball players are nearly twice as likely to stop using spit tobacco when dentists or dental hygienists, as well as their teammates, actively intervene than the attention of politicians who are hotly when they don’t, a new University of California at San Francisco study has found. debating health care issues on Capitol The study, reported at the International Association for Dental Research meeting, Hill. Rep. Greg Ganske, R-Iowa, who found that 27 percent of spit tobacco users stopped using the potentially cancer-causing co-authored the Patient’s Bill of Rights, substance for at least one year when dental health professionals, with the help of distributed a copy of Bierstock’s “Minimal teammates, intervened. About 14 percent of the athletes who received no intervention Service” CD to every member of Congress, quit using spit tobacco, which includes chewing tobacco and snuff. noting in an attached letter that “a little The study tracked baseball players at 44 high schools throughout rural California. levity always helps when you are discuss- ing the subject of health care.” Dental health professionals intervened at 22 of those schools. There was no intervention Bierstock agrees and has used this at the other 22. premise to embark on a national tour “High school baseball players who participated in a peer-led team discussion of the that has taken him and his band across negative health effects of spit tobacco use, and who received an oral cancer screening the country to medical conventions and exam by a dentist or dental hygienist who pointed out to players sores in their mouths corporate events to spread his message. related to spit tobacco use and advised them to stop their tobacco use, were twice as “I realized the medical profession was likely to stop using than those players who received nothing,” says Margaret Walsh, EdD, in serious need of a good laugh,” Bierstock UCSF professor of dental public health and the study’s principal investigator. says. “But we’re also trying to help people The study’s results, Walsh said, show that oral health experts must become more understand how managed care really aggressively involved in teaching youths the risk of using spit tobacco. works -- or perhaps why it doesn’t.” The study was funded by California’s tobacco tax. The “Mastoid Sally” CD single costs $4.25 plus shipping and handling and can be ordered by calling (888) 426-7529 or from Bierstock’s web site at www.man- agedmusic.com. Original songs from Dr. Sam and the “Beyond HMOs: the Outlook for cent from 1997. Explaining the industry’s Managed Care Blues Band include: Managed Care in 2001,” published by recent woes, authors Carl Mercurio and nn“You Picked a Fine Time to Leave Me Corporate Research Group, Inc., forecasts Efrem Sigel note, “With HMOs enrolling Blue Shield” a six-fold increase in industry profits in more elderly, poor and sick members, nn“You’re One Hip Mama (‘Cause They 1999, to more than $2 billion. utilization soared, as did medical costs. ... Won’t Pay for Two)” With premiums expected to rise 8 per- Profit margins shrank. ... Mega-mergers nn“I’d Love to Kiss You Baby, but I Just cent to 9 percent in 1999, the report says, aimed at improving financial performance Came Across Your Medical Records on the managed care industry can expect often had the opposite effect.” the Internet” revenue growth of 15 percent to reach a Over the next three years, large man- nn“If You Won’t Refuse Treatment We’ll projected $173 billion in 1999 revenues. aged care companies will continue to Find Someone Who Will” The three largest for-profit managed care prune operations, such as money-losing nn“What Now My Glove” (a digital companies are United HealthCare, with Medicare or Medicaid plans. “Successful recording) projected 1998 revenues of about $17 companies will have to meet escalating de- Managed Care Profits Expected to billion; Aetna U.S. Healthcare, projected mands for quality” while controlling costs, Rebound in 1999 revenues of $14 billion; and Cigna Life & and will have to satisfy “multiple constitu- Higher premiums will return the man- Health, projected revenues of $12 billion. encies of members, employers, providers, aged care industry to modest profitability Kaiser, with revenues of $14.6 billion, is government regulators and investors and after four tough years, a new study finds, the largest not-for-profit. creditors,” the report says. It predicts that but the market “will ruthlessly weed out Corporate Research Group projects dozens of HMOs will go out of business under-performing organizations, both that the managed care industry will finish by 2001. not-for-profit and for-profit.” 1998 with 765 million members, up 8 per-

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Pack Your Bags and Make Your CPA your best promotional device: “In order to finance their education, Smile nnIt’s your first (and sometimes only) many students are borrowing $20,000 Taking your spouse to Paris for a big piece of promotional material, usually per year or more just to cover the costs of dental meeting is one way of writing off printed as soon as the business starts. tuition and expenses,” says David J. Ful- your anniversary trip, but it’s not the only nnIt is your cheapest advertisement -- a ton, DDS, a general dentist in Waukegan, option. boxful goes a long way. Ill., and president of the Chicago Dental “Mixing business with pleasure is one nnIt has a wide targeted distribution -- it’s Society. “That makes it incredibly tough to of the wisest tax moves you can make,” mostly handed out face-to-face. make payments on loans while trying to according to Ken Rubin, CPA. “It’s fun and nnIt sets the business’ style and format, open an office and establish a dental prac- easy to structure your vacations so they’ll which is then echoed on stationery and tice. Some new dentists just don’t make be tax deductible.” products. it. I would hope that dental schools would The most obvious way to do that is nnIt is a basic sales tool, uncomplicated step up their efforts to tackle the problem to attend dental continuing education and flexible. of student debt.” seminars and conventions in places nnIt is the most frequently used Following are other statistics from the such as Hawaii and Aspen, Rubin says in marketing tool for small businesses. 1997 Survey of Dental School Seniors: Facets, August/September 1998. A less nnFor many businesses, it generates more nn13.3 reported no debt. obvious method is visiting dental offices patients and referrals than any other nn6.8 percent reported debt of $0 to at the vacation destination. According form of advertising. $30,000. to Rubin, if you can establish that the nnIt is versatile. It is easy, quick and nn10.6 percent reported debt of $30,000 primary purpose of your trip was to visit inexpensive to tailor for different to $50,000. dental offices, the trip is tax-deductible. markets or purposes. nn23.6 percent reported debt of $50,000 Some reasons for visiting the offices could nnIt is expected. Business cards are an to $80,000. include observations and discussions with established business practice that can nn17.5 percent reported debt of $80,000 dentists about the following items: also serve as an appointment card. to $100,000. nnOffice design; nnIt creates name recognition, nn18.7 percent reported debt of $100,000 nnEmployment or partnership personalizes you, and builds credibility. to $150,000. opportunities; nn9.5 percent reported debt of more than nnMarketing methods; The Price Also Rises $150,000. nnSpecific dental procedures; and New dentists who graduate from When the 13.3 percent of students nnPractice management issues. dental school and prepare to establish who report no debt are omitted from Rubin strongly recommends get- their own practices are on average $81,688 statistics, the average graduating debt in ting follow-up letters from the dentists in debt, according to the 1997 Survey of 1997 rises to $94,182. you meet, detailing what was discussed. Dental School Seniors produced by the According to Rubin, you are required Chicago-based American Association of Link Between Chlamydia and TMJ is to spend at least four hours per day on Dental Schools. Found business-related matters for the entire day That figure, which includes students The bacterium Chlamydia trachoma- to qualify as a business day. If your spouse from private, public and private/state- tis, which is the leading cause of pelvic is employed by your practice, his or her related schools, represents a 7.8 percent inflammatory disease and its resulting expenses can also be deducted. increase from 1996. In contrast, graduat- infertility, may also cause TMJ dysfunc- Because tax rules related to travel ing debt in 1980 was $18,500. tion. This condition affects 10 million are complicated, Rubin urges dentists to First-year tuition and fees have in- Americans, the vast majority of whom are consult their CPAs to help with the tax creased an average of 6 percent each year women, according to the National Insti- planning aspects of vacations. since the 1989-90 academic year. Average tutes of Health. first-year tuition costs for the 1996-97 aca- A research team led by oral and maxil- The Mighty Mouse of Marketing demic year were $12,771 for residents and lofacial surgeon Dr. Charles Henry is the Ten reasons why your business card is $20,709 for students who live out-of-state. first to identify the presence of Chlamydia

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trachomatis in human temporomandibu- lar joint tissue, finding the bacterium significantly more prevalent in patients with TMJ dysfunction than in the general population. Henry, assistant professor at the Goldman School of Dental Medicine at Boston University, presented these results at the American Association of Oral and Maxillofacial Surgeons annual meeting in September. Chlamydia is the most common sexu- ally transmitted bacterium in the United States with an estimated 5 million cases per year. If recognized early, it can be effectively treated with a simple course of antibiotics. “Our study indicates that chlamydia-in- duced arthritis may cause TMJ dysfunction and pain in many patients,” Henry says. Since chlamydia is frequently as- sociated with sexually acquired reactive arthritis, its presence in the TMJ tissue suggests that TMJ dysfunction may be a previously unrecognized form of reactive arthritis.

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Current Views on Periodontal Therapy

David F. Levine, DDS

he more things change, the The point is not to denigrate the use therapy, traditionally, there has been more they remain the same. of periodontal membranes. The use of discussion and controversy associated Although periodontal therapy membranes for regeneration does have its with the different treatment methods has undergone many changes place in the armamentarium used to treat utilized. Dr. Filippelli and I address this in the past decade, the basics periodontal disease. However, time has controversy, as well as discuss surgical Tof periodontal therapy remain the same. shown that periodontal regeneration with pocket therapy directed toward pocket Periodontal disease is primarily a bacterial membranes is not the panacea we had all reduction through recontouring the infection. No matter what therapeutic hoped for. Time has again proven that underlying bone. modality is used, the main goal of therapy the standard treatment modalities for Dr. Perry Klokkevold discusses the must be to reduce and then maintain periodontal therapy may still be the most new approaches to the diagnosis and the bacterial load at a level that the host effective. This is not to say that future treatment of periodontal disease in light (patient) can successfully defend. It may, therapeutic modalities will not bring of dentistry’s improved understanding of in fact, be true that the most important about significant changes in the way we the pathogenesis and appreciation for the factor in successful periodontal therapy treat periodontal disease. However, at the influence of host factors. is not the therapeutic modality, but the present time, the standard therapeutic Finally, Dr. Handelsman, Dr. Ravon, post-treatment maintenance program. modalities are the only methods that have and I discuss surgical crown lengthening. During the past decade, the research stood the test of time. Therefore, this Surgical crown lengthening is one of the on and treatment of periodontal disease issue of the Journal of the California Dental most important periodontal surgical has been heavily weighted toward Association is dedicated to reviewing some therapies, yet seems to be one of the regeneration. Periodontists were quick to of the standard therapeutic modalities least performed. Dr. Handelsman, Dr. jump on the bandwagon of regeneration used in the treatment of early to Ravon and I discuss the indications for as the “new and improved” treatment moderate periodontitis. crown lengthening, as well as several of of periodontitis. At previous national As a review of the current views about the benefits of completing it prior to final periodontal meetings, a significant periodontal regeneration, Dr. William preparation of the permanent restoration. number of the lectures were about using Becker discusses regeneration of lost It is hoped that these articles will periodontal membranes to regenerate lost periodontal structures using different help bring the reader up to date on some periodontal structures. In the evening, materials. Dr. Becker has been involved of the current views on these topics. It companies gave lavish parties to promote with much of the research regarding is important to be aware that some of their regeneration products. periodontal regeneration. He reviews these topics were included in this journal At the most recent national current literature regarding regeneration because it was believed that they would periodontal meeting, very few of the and discusses whether regeneration is bring about controversy. It is hoped that lectures were about regeneration using really possible. through discussion of the controversies, periodontal membranes. No lavish parties Dr. Greg Filippelli and I discuss we may all expand our knowledge of the were given, and one company was even osseous resective surgery as a surgical treatment of periodontal disease. Whether giving away their membranes. Their treatment option to treat early to you strongly agree or disagree with the profits were down, and they were no moderate periodontitis. While the position of the articles in this journal, if longer planning on selling membranes for concept of pocket reduction is a something is learned, my goal in putting regeneration. fundamental objective of periodontal this journal together has been reached.

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Periodontal Regeneration: Myth or Reality

William Becker, DDS, MSD

abstract One of the goals of periodontal therapy is regeneration. During the past 20 years, several materials and techniques have been developed and tested for enhancing periodontal regeneration. This paper evaluates flap , allogenic and alloplastic grafting, and the use of nonresorbable and resorbable barrier membranes as regenerative techniques. One of the most predictable regenerative therapies is treatment of the three-walled intrabony defect. This defect can be repaired with 2 to 2.5 mm of bone fill and results in significant gains in clinical probing attachment and decreases in probing depths. There is a slightly greater improvement in periodontal measures with barrier membranes. Commercial preparations of allogenic bone and alloplastic fillers have a long, safe history of use and are primarily osteoconductive. They decrease probing depths and provide short-term gains in clinical attachment levels. Barrier membranes provide short-term evidence of improving Class II furcation invasions, however there is insufficient evidence that these improvements are sustained long-term. Class III furcations are not predictably treated by regenerative therapies. To date, there is an absence of clinical evidence that regenerative therapy increases the long-term life span of teeth.

egeneration is one of the The purpose of this paper is to evaluate primary goals of periodontal periodontal regenerative procedures and author therapy. During the past determine their patient benefits. William Becker, DDS, 20 years, there has been MSD, is a clinical associate an explosion of techniques Defect Anatomy professor in periodontics Rand materials designed to increase the Prichard described the classic at the University of predictability of periodontal regeneration. intrabony defect as having three bony Southern California School Regeneration is defined as restoration walls, with the root forming the fourth of Dentistry and a clinical 1 professor in periodontics of lost parts. Periodontal regeneration wall. The defect has definite limits and 2 3 at the University of requires the restitution of with does not extend into the furcation. Saari Texas at Houston. He inserting fibers and bone. Repair implies and Tal4 examined dry skulls and described also maintains a private healing by long . the frequency and location of intrabony practice, limited to Unfortunately, regeneration can only defects. These defects were frequently periodontics, in Tucson, Ariz. be ascertained by histologic evaluation, found distal to mandibular second molars. hence most of the procedures designed Alveolar bone in this location has thick for regeneration probably result in cortical plates with varying quantities repair. Studies using filler materials have of cancellous bone. In the presence of demonstrated improved periodontal inflammation, cancellous bone resorbs, measures. To date, none of these studies leaving a bony crypt surrounded by a has provided evidence that filler materials varying number of bony walls. increase the life span of the treated teeth. 118 february 1999 regeneration

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Figure 1a. Figure 1b. Deep three An ePTFE barrier wall intrabony has been fitted to defect distal to cover the defect. the mandibular second molar. The defect is Open Flap Debridement contained, and furcation is not 5 Carranza and Prichard2 are credited involved. with presenting successful treatment of classic three-wall intrabony defects. These defects are surrounded by bone on three sides, with the root forming the fourth wall. Prichard followed successfully treated patients for more than 30 years. Examination of case reports demonstrated clinical evidence of bone fill. These defects appeared to be deep and were primarily located distal to mandibular second molars. Polson and Heijl6 reported an average gain of 2.5 mm of bone after treatment of deep two- and two-to-three-wall intrabony defects. Becker and colleagues7,8 reported clinical findings after treatment of 36 consecutive three-wall defects. These defects were deeper than 5 mm and were wide. The average gain of bone fill was 2.5 mm, with significant decreases in clinical probing depth. Figure 1c. The defect was re-entered 11 months after Figure 1d. The initial defect appears wide and extends Treatment of these defects by flap treatment to reduce a residual defect. Note defect bone fill. close to the root apex. debridement requires an understanding of anatomy, a thorough clinical examination, with interrupted sutures. Postoperatively, and identification of etiologic factors. The patients can be placed on antimicrobial diagnosis and treatment depends upon rinses, and the sutures are removed in evaluation of probing depths, clinical a week. is reinstituted and attachment levels, and good periapical the area is evaluated by probing and radiographs. Defect depth can frequently radiographic examination after nine be estimated from radiographs. In defects months of healing. These defects likely greater than 5 mm, the presence of repair with a long junctional epithelium. subgingival and positive tooth vitality are indications that treatment will Allografts and Alloplasts Figure 1e. Eleven-month follow-up X-ray. Note slight result in a favorable outcome. residual defect and extensive amount of bone fill. During the 1970s, the use of alloplastic Surgical treatment consists of elevation filler and allogenic bone were introduced of full-thickness mucoperiosteal flaps for treatment of periodontal defects.10-17 and thorough defect and root surface Freeze-dried bone became a popular filling debridement. This is performed with a walls. He reported that bony walls of the material, since early reports indicated combination of rotary and ultrasonic same height never surround three-walled this material was osteoinductive. The instruments. The defect is probed using intrabony defects. He recommended that principle of osteoinduction means the lowest wall as reference. If the the highest wall be reduced to the level of that bone morphogenetic proteins or defect is greater than 5 mm, it is a good the adjacent walls. Adjusting the bony walls other growth factors or proteins can candidate for repair by flap debridement. should allow for complete repair of the affect undifferentiated mesenchymal Ochsenbein9 described the relationship defect. The clot is then allowed to stabilize cells to differentiate into cartilage and of the defect to the surrounding bony after which the flap margins are sutured subsequently bone.

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Urist, in a series of rodent studies, first described bone formation in ectopic sites (muscle tissue) by induction.18-20 Urist isolated a complex series of inductive proteins known as bone morphogenetic Figure 2a. Radiograph demonstrates deep, intrabony Figure 2b. Buccal view, showing inconsistent bony 20, 21 proteins. The indications, expectations, defect distal to the maillary right first bicuspid. margin. and contraindications of when and where to use allogenic bone became confusing. Numerous clinical studies have demonstrated that placement of allografts into periodontal defects will result in decreased probing depths, bone fill, and gains in clinical attachment levels.13,14,22 Other investigators have presented histologic evidence of periodontal regeneration following implantation of demineralized bone matrix.15,23 When interproximal defects were treated with Figure 2c. Palatal view demonstrates contained, three- Figure 2d. An ePTFE has been used either barrier membranes alone or with walled intrabony defect. to isolate the defect. allogenic bone, the results were similar.24 Unfortunately, clinical studies do not hence replacement by substitution is demonstrate evidence of bone induction highly variable. Healing of defects treated by the implanted material. Recently bone with allogenic bone implants likely occurs induction with commercially available by repair. This may be sufficient to prolong allogenic bone has been questioned.25-27 the life span of the tooth. There is sufficient scientific evidence Investigators created furcation defects that commercially available bone matrix in baboons.28 They implanted bone has varying amounts of bone-inductive morphogenetic proteins extracted from activity. The capacity of the bone implants bovine demineralized bone utilizing the to initiate bone induction diminishes demineralized matrix as the carrier for test Figure 2e. Three-year follow-up radiograph with age and varies from batch to batch. sites. Collagen matrix alone was used for demonstrating bone fill of original defect. Compare with The quantity of bone matrix proteins or control defects. Figure 2a. other growth factors or proteins necessary Histologic evaluation of treated to induce clinically relevant amounts defects indicated significant periodontal of bone is unknown. Commercially regeneration within the test furcations; available bone allografts can be considered however, large quantities of unresorbed osteocondutive. When the allogenic bone demineralized matrix carrier was present particles are in contact with host bone over within the surrounding connective tissue. these fillers. Treatment of periodontal time, new bone will surround the bone Alloplastic materials are synthetic defects with filler materials results in matrix particles. Allogenic bone away from bone substitutes. These materials are decreased probing depths, gains in clinical native bone will remain unresorbed for biocompatible, osteoconductive, and attachment levels, and radiographic long periods. There is insufficient evidence either resorbable or nonresorbable. They evidence of “bone like” material within the to indicate that graft particles will ever are of questionable value as regenerative defects. The defects heal by repair. Long- be totally replaced by host bone. There is materials. They can effectively be used for term follow-up studies of teeth treated also insufficient evidence to indicate that ridge augmentation, providing that dental with these materials are not available, and allografts will be resorbed by osteoclasts, implants do not significantly contact the patient benefits are questionable.

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Figure 3a. A Class II furcation with a narrow buccal Figure 3b. Defect filled with demineralized freeze-dried Figure 3c. A barrier membrane was fitted over bone- after debridement bone. filled defect.

Guided Tissue Regeneration Scandinavian investigators introduced the principle of guided tissue regeneration.29-35 The concept was based on isolating periodontal defects with barrier membranes. The purpose of the barriers was to exclude epithelial down-growth and to allow periodontal ligament cells to repopulate the previously diseased Figure 3d. Flaps sutured in an attempt to completely Figure 3e. Patient was maintained at four-month root. The first commercial barrier cover the barrier membrane. intervals for six years. Defect probed during a maintenance visit. Note proble penetration into furcation. Probing depth membranes were made of expanded reduction originally recorded postoperatively has been lost. polytetrafluoroethylene (ePTFE) (WL The defect probes to the original depth. Gore and Associates, Flagstaff, Ariz.) and were cell-occlusive. There was an open microstructure collar that was fitted around the tooth at or near the cementoenamel junction. The biologic rationale for using these barriers was based on scientific and clinical studies. These barriers have been used to treat intrabony and furcation defects.32,33,35-44 Results after treatment of multiwalled defects with debridement and barrier membranes Figure 3f. Preoperative radiograph taken in 1990 Figure 3g. Radiograph taken at follow-up visit in 1996. demonstrated improved probing depths Compare with tradiographi taken in 1990. There was no and gains in clinical attachment levels apparent change in the furcation status. with varying amounts of reported bone fill (Figures 1 and 2). Several studies provided evidence of sustained gains in clinical measures when compared with the short- bone.45-47 The primary reason for adding the freeze-dried bone and an ePTFE barrier. term reports. bone implants was to support the barrier Probing depth had decreased by the Barrier membrane treatment of membranes. Barrier membranes with nine-month evaluation. The patient was furcation defects is technique-sensitive. allografts have primarily been used to treat maintained for six years with progressive There is minimal evidence of complete furcation defects. Studies that compared loss of the initial soft tissue gains in furcation closure with or without allogenic debridement alone with barriers plus grafts clinical probing attachment and a return bone alone or with barrier membranes.40,42 generally demonstrated similar results.48,49 to preoperative probing depth. Failure to There are several reports in which barrier Figure 3 demonstrate a furcation defect predictably close Class II furcations and membranes have been used with allogenic that was treated with a demineralized the tendency for initial probing depth

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18. Urist MR, Bone: formation by autoinduction. Science decreases to regress to pretreatment for improving results from periodontal 150:893-9, 1965. depths has brought into question the long- regenerative procedures. When these 19. Urist MR and Dowell TA, The newly deposited mineral in cartilage and bone matrix. Clin Orthop 50:291-308, 1967. term patient benefits of treating furcation procedures are critically evaluated, they 20. Urist MR, Silverman BF, et al, The bone induction principle. defects with barrier membranes alone or appear to have slightly better clinical Clin Orthop 53:243-83, 1967. in combination with allografts. Moderately outcomes than flap debridement 21. Urist MR, Dowell TA, et al, Inductive substrates for bone formation. Clin Orthop 59:59-96, 1968. involved Class II defects can be effectively procedures. These slight improvements 22. Anderegg CR, Martin SJ, et al, Clinical evaluation of the use treated with open flap debridement, may not provide cost or patient benefits in of decalcified freeze-dried bone allograft with guided tissue however long-term patient outcomes terms of improved periodontal health and regeneration in the treatment of molar furcation invasions. J Periodontol 62:264-8, 1991. are unknown. There are no predictable may not increase the health or longevity of 23. Bowers GM, Schallhorn RG, and Mellonig JT, Histologic methods for treating Class III furcations the treated teeth. evaluation of new attachment in human intrabony defects, a with regenerative procedures. literature review. J Periodontol 53:509-14, 1982. 24. Gouldin AG, Fayad S, and Mellonig JT, Evaluation of References guided tissue regeneration in interproximal defects, Part 1. Melcher T, On the repair potential of periodontal tissues. J II: membrane and bone versus membrane alone. J Clin Bioabsorbable Barriers Periodontol 47:256-60, 1976. Periodontol 23:485-91, 1996. Nonresorbable barriers required a 2. Prichard JF, The diagnosis and management of vertical bony 25. Shigeyama Y, D’Errico JA, et al, Commercially prepared defects. J Periodontol 54:29-35, 1983. second minor surgery for removal. These allograft material has biological activity in vitro. J Periodontol 3. Saari J, Hurt W, and Biggs N, Periodontal bony defects on the 66:478-87, 1995. membranes frequently became exposed dry skull. J Periodontol 39:278-83, 1968. 26. Becker W, Becker BE, and Caffesse R, A comparison of and plaque-infected. When this occurred, 4. Tal H, The prevalence and distribution of intrabony defects demineralized freeze-dried bone and autologous bone to in dry mandibles. J Periodontol 55:149-54, 1984. there was less improvement in clinical induce bone formation in human extraction sockets [published 5. Carranza F, A technique for reattachment. J Periodontol erratum appears in J Periodontol 66(4):309, Apr 1995] [see measures when compared with sites where 25:272-5, 1954. comments]. J Periodontol 65:1128-33, 1994. the membranes remained unexposed.50-52 6. Polson AM and Zander HA, Effect of periodontal trauma 27. Becker W, Urist MR, et al, Human demineralized freeze- upon intrabony pockets. J Periodontol 54:586-91, 1983. As a consequence of these problems, a dried bone: inadequate induced bone formation in athymic 7. Becker W, Becker BE, and Berg L, Repair of intrabony defects mice, a preliminary report. J Periodontol 66:822-8, 1995. new generation of barrier membranes was as a result of open debridement procedures, report of 36 28. Ripamonti M, Heliotis B, et al, Bone morphogenetic developed. These barriers resorb and are treated cases. Int J Periodontics Restorative Dent 6:8-21, 1986. proteins induce periodontal regeneration in the baboon (Papio 8.Becker W, Becker BE, et al, Clinical and volumetric analysis of manufactured from either polyglycolic ursinus). J Periodontol Res 29:439-45, 1994. three-wall intrabony defects following open flap debridement. 29. Nyman S, Bone regeneration using the principle of guided and polylactic acids, collagen, or various J Periodontol 57:277-85, 1986. tissue regeneration. J Clin Periodontol 18:494-8, 1991. combinations of these. Resorbable barriers 9. Ochsenbein C, Combined approach to the management 30. Karring T, Nyman S, et al, Potentials for root resorption of intrabony defects. Int J Periodontics Restorative Dent have been used to treat intrabony as well during periodontal wound healing. J Clin Periodontol 11:41-52, 15:328-43, 1995. 1984. as furcation defects. Results from studies 10. Meffert RM, Thomas JR, et al, Hydroxylapatite as an 31. Karring T, Isidor F, et al, New attachment formation on comparing nonresorbable to resorbable alloplastic graft in the treatment of human periodontal teeth with a reduced but healthy periodontal ligament. J Clin osseous defects. J Periodontol 56:63-73, 1985. membranes demonstrate comparable Periodontol 12:51-60, 1985. 11. Meffert RM, Thomas JR, and Caudill RF, Hydroxyapatite 53 32. Gottlow J, Nyman S, et al, New attachment formation as results. Intrabony defects were treated implantation -- clinical and histologic analysis of a treated the result of controlled tissue regeneration. J Clin Periodontol with resorbable barriers and compared lesion and speculations regarding healing phenomena. Int J 11:494-503, 1984. Periodontics Restorative Dent 6:60-6, 1986. with flap debridement controls.54 33. Gottlow J, Nyman S, et al, New attachment formation in 12. Yukna RA, Mayer ET, and Brite DV, Longitudinal evaluation the human by guided tissue regeneration, case Findings indicated improved clinical of durapatite ceramic as an alloplastic implant in periodontal reports. J Clin Periodontol 13:604-16, 1986. measures for probing depth reduction osseous defects after three years. J Periodontol 55:633-7, 34. Gottlow J, Nyman S, and Karring T, Maintenance of new 1984. and clinical attachment level gains. These attachment gained through guided tissue regeneration. J Clin 13. Mellonig JT, Decalcified freeze-dried bone allograft as Periodontol 19:315-7, 1992. improvements were not significantly an implant material in human periodontal defects. Int J 35. Gottlow J, Guided tissue regeneration using bioresorbable enhanced with guided tissue regeneration Periodontics Restorative Dent 4:40-55, 1984. and nonresorbable devices: initial healing and long-term 14. Mellonig JT, Periodontal bone graft technique. Int J therapy. results. J Periodontol 64:1157-65, 1993. Periodontics Restorative Dent 10:288-99, 1990. 36. Becker W, Becker BE, et al, New attachment after 15. Bowers GM, Granet M, et al, Histologic evaluation of new treatment with root isolation procedures: report for treated Conclusion attachment in humans, a preliminary report. J Periodontol Class III and Class II furcations and vertical osseous defects. 56:381-96, 1985. Technological and surgical techniques Int J Periodont Restorative Dent 8:8-23, 1988. 16. Bowers GM, Chadroff B, et al, Histologic evaluation of 37. Becker W, Dahlin C, et al, The use of e-PTFE barrier have been implemented to enhance new attachment apparatus formation in humans, Part III. J membranes for bone promotion around titanium implants periodontal regeneration. Results from Periodontol 60:683-93, 1989. placed into extraction sockets: a prospective multicenter 17. Bowers GM, Chadroff B, et al, Histologic evaluation of these advances were met with enthusiasm study. Int J Oral Maxillofac Implants 9:31-40, 1994. new attachment apparatus formation in humans, Part II. J 38. Cortellini P, Pini Prato G, and Tonetti MS, Periodontal because they provided the possibility Periodontol 60:675-82, 1989.

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regeneration of human infrabony defects, Part II: re-entry procedures and bone measures. J Periodontol 64:261-8, 1993. 39. Cortellini P, Pini Prato G, and Tonetti MS, Periodontal regeneration of human infrabony defects, Part I: clinical measures. J Periodontol 64:254-60, 1993. 40. Pontoriero R, Nyman S, et al, Guided tissue regeneration in the treatment of furcation defects in man. J Clin Periodontol 14:618-20, 1987. 41. Pontoriero R, Lindhe J, et al, Guided tissue regeneration in degree II furcation-involved mandibular molars, a clinical study. J Clin Periodontol 15:247-54, 1988. 42. Pontoriero R, Lindhe J, et al, Guided tissue regeneration in the treatment of furcation defects in mandibular molars, a clinical study of degree III involvements. J Clin Periodontol 16:170-4, 1989. 43. Pontoriero R and Lindhe J, Guided tissue regeneration in the treatment of degree III furcation defects in maxillary molars. J Clin Periodontol 22:810-2, 1995. 44. Pontoriero R and Lindhe J, Guided tissue regeneration in the treatment of degree II furcations in maxillary molars. J Clin Periodontol 22:756-63, 1995. 45. Schallhorn RG and McClain PK, Combined osseous composite grafting, root conditioning, and guided tissue regeneration. Int J Periodontics Restorative Dent 8:8-31, 1988. 46. Schallhorn RG and McClain PK, Clinical and radiographic healing pattern observations with combined regenerative techniques. Int J Periodontics Restorative Dent 14:391-403, 1994. 47. McClain PK and Schallhorn RG, Long-term assessment of combined osseous composite grafting, root conditioning, and guided tissue regeneration. Int J Periodontics Restorative Dent 13:9-27, 1993. 48. Mellado JR, Salkin LM, et al, A comparative study of ePTFE periodontal membranes with and without decalcified freeze- dried bone allografts for the regeneration of interproximal intraosseous defects. J Periodontol 66:751-5, 1995. 49. Wallace SC, Gellin RG, et al, Guided tissue regeneration with and without decalcified freeze-dried bone in mandibular Class II furcation invasions. J Periodontol 65:244-54, 1994. 50. Nowzari H and Slots J, Microbiologic and clinical study of polytetrafluoroethylene membranes for guided bone regeneration around implants. Int J Oral Maxillofac Implants 10:67-73, 1995. 51. Nowzari H, Matian F, and Slots J, Periodontal pathogens on polytetrafluoroethylene membrane for guided tissue regeneration inhibit healing. J Clin Periodontol 22:469-74, 1995. 52. Nowzari H, MacDonald ES, et al, The dynamics of microbial colonization of barrier membranes for guided tissue regeneration. J Periodontol 67:694-702, 1996. 53. Becker W, Becker BE, et al, A prospective multi-center study evaluating periodontal regeneration for Class II furcation invasions and intrabony defects after treatment with a bioabsorbable barrier membrane: one-year results. J Periodontol 67:641-9, 1996. 54. Bratthall G, Soderholm G, et al, Guided tissue regeneration in the treatment of human intrabony defects, clinical, radiographical and microbiological results, a pilot study. J Clin Periodontol 25:908-14, 1998. To request printed copies of this article, please contact: William Becker, DDS, MSD, 801 N. Wilmot, B-2, Tucson, AZ 85711

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A Review of Osseous Resective Surgery

David F. Levine, DDS, and Greg Filippelli, DDS

abstract The treatment of periodontal diseases associated with attachment loss has involved a variety of approaches. While the goal of periodontal surgical treatments is to access the root surfaces for proper debridement, the decision to remove or reshape the supporting bone has been controversial. This paper will address the controversy as well as discuss surgical pocket therapy directed toward pocket reduction through recontouring the underlying bone.

authors ver the years, the treatment periodontal surgical treatments have as of periodontal diseases their main goal to access the root surfaces David F. Levine, DDS, Greg Filippelli, DDS, is an assistant clinical is an associate clinical associated with attachment for proper debridement, it is the decision professor at the University professor at the USC loss has involved numerous to remove or reshape the supporting bone of Southern California School of Dentistry surgical and nonsurgical that has produced the most controversy. School of Dentistry. He and attending staff Oapproaches. Although the concept of This paper will address this controversy, also maintains a private periodontist at the Los pocket reduction is a fundamental as well as discuss surgical pocket therapy practice in Toluca Lake, Angeles County/USC Calif. Medical Center. He also objective of periodontal therapy, directed toward pocket reduction through maintains a private discussion and controversy have been recontouring the underlying bone. practice in Rancho associated with the different treatment Schluger is often credited with first Cucamonga, Calif. methods used. Several surgical treatment describing osseous resective therapy. modalities have been proposed to treat In 1949,1 he attempted to describe and the soft tissue lesions associated with identify the rationale for and technique periodontitis as well as to gain access of osseous resective surgery for pocket to the root and supporting bone. These elimination. He stated that total pocket include the apically positioned flap elimination could be maintained only with and without osseous resection, with the removal of the bony component modified Widman flap surgery, open flap of the pocket. He further advocated the curettage, and several other repositioned- need to reshape the bone to a physiologic flap procedures. While most of these form resembling the pattern of horizontal

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atrophy. Otherwise, the gingiva would and the underlying bone, the difference is the attachment apparatus, is removed not adapt adequately; and pockets, expressed in pocket depth. If the gingival to eliminate a periodontal pocket and especially interproximally, would re- tissues are contoured to the form of the establish gingival contours that will be establish. In 1935, Carranza2 advocated a diseased osseous crest, the irregularities maintained. Ostectomy requires the loss mucoperiosteal flap approach and listed created in the gingiva would not be of some bony support of the tooth or specific indications where bone should maintained. In time, the soft tissue teeth, and the amount involved will be an be surgically remodeled to stimulate the will round out and revert to its original important criterion for its use. rebuilding of healthy support around scalloped pattern. The terms positive architecture and the teeth. Since then, several people This soft tissue proliferation results negative architecture are also widely have talked about and defined osseous in pocket depth. Residual increased used when discussing osseous surgery. resective therapy. The World Workshop pocket depths are more likely to break These terms describe the position of in Periodontics defines osseous surgery down, need constant and meticulous the interdental bone in relation to the as “that aspect of periodontal surgery treatment in the office and at home, and radicular bone. Positive architecture refers which deals with the modification of present a potential nidus for reinfection. to a situation in which the osseous crest the bony support of the teeth.”3 Sims To be truly successful in reducing pocket follows the shape of the cementoenamel and Carranza define osseous surgery depths, the reshaping of bone must be junctions, that is, the interdental bone as the procedure by which changes in done with curves and slopes that mimic is more coronal than the radicular the alveolar bone can be accomplished the contours of the healthy gingiva. The bone. Negative architecture is used to to rid it of deformities induced by the tendency of gingiva to assume a pre- describe a situation in which the osseous periodontal disease process or other existing form dictates the architecture of crest does not follow the shape of the related factors, such as exostosis and the bone that must be created to achieve cementoenamel junctions, that is, the tooth supraeruption.4 Friedman described a stable result. Therefore, the eradication interdental bone is more apical than the osseous surgery as surgical removal of of the periodontal pocket is dependent radicular bone. The discrepancies between the gingiva and reshaping of the bone upon the correction of the underlying the shape and position of the osseous to eliminate the pocket and correct bony deformity. Surgical elimination crest and the result in unphysiologic architecture.5 What all of the pocket with resultant minimal pocket depths. these definitions have in common is that probing depths allows the patient access Indications for osseous surgery as the goal of osseous surgery is to produce for proper plaque control and facilitates described by Carranza and Carranza osseous contours that are consistent with maintenance by the therapist. This is the Jr.6 are to recontour bone that forms the shape and form of the healthy gingival basis of osseous resective surgery. part of the outer wall of the pocket, to tissues. By creating a bony architecture Procedures used to correct osseous prevent recurrence of the pocket, and to that mimics the final shape of the gingiva, defects have been classified into two reshape the alveolar crest, establishing it is thought that pocket reduction cannot groups. In 1955, Friedman defined a normal fiber arrangement. Indications only be obtained, but also maintained. these two procedures as osteoplasty for osteoplasty according to the World Gingival tissue is elastic, that is, it and osteoectomy.5 Friedman defined Workshop in Periodontics3 are buccal or tends to return to its original architectural osteoplasty as a plastic procedure in which lingual bony ledges, tori, etc.; intrabony contours. Even when deep pockets the periodontal pocket is eliminated defects associated with tilted molars; exist, the gingiva will retain a scalloped and the bone reshaped to achieve shallow buccal or lingual intrabony form that follows the shape of the physiologic contour of the bone and the defects; flat interproximal areas; the cementoenamel junction. This form is gingiva overlying it. In this operation, elimination of deep interproximal independent of the underlying contours the bone that is reshaped is not part of defects to achieve physiological contour; of the osseous crest. When the gingiva has the attachment apparatus, thus no bony incipient furcation involvements; and for its normal architecture and the underlying support of the tooth or teeth is lost. improvement of alveolar contours for flap bone has a similar architecture, there is a Friedman defines osteoectomy (also adaptation. Ostectomy has been indicated shallow probing depth. When there is a referred to as ostectomy), as an operative for the elimination of interdental craters, discrepancy between the gingival tissue procedure in which bone that is part of intrabony pockets not amenable to

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reattachment procedures, horizontal craters overall include the facts that the Other contraindications for surgery alveolar bone loss with irregular marginal interdental areas are more difficult to are inadequate plaque control by the bone height, and moderate and advanced clean, and only a small percentage of patient, noncompliance with supportive furcation involvement.3 people floss regularly. Other possible periodontal therapy, and certain medical The most common indication for explanations include the lack of and anatomic conditions. osseous resective surgery is to treat the keratinization of the gingival col area and Although the concept of osseous shallow two-wall osseous crater. Osseous vascular patterns from the gingiva to the surgery was introduced into the United craters are concavities in the crest of the center of the crest that may provide a States in the late 1940s, a critical interdental bone that are confined within pathway for inflammation.7-9 description of surgical guidelines, the facial and lingual walls of the alveolus. Contraindications for osseous tenets, and limitations was essentially Practically all craters have a slope from resective surgery include deep osseous unavailable for decades. The lack buccal and lingual walls to the base. These craters, three-wall osseous defects, of standardized guidelines and the slopes represent more than two-thirds of moderate to deep circumferential defects, variability in surgical technique among the crater. and bony defects situated on the buccal clinicians made it difficult to scientifically The site of the initial periodontal aspect of terminal mandibular molars compare the effectiveness of the lesion is usually the interproximal area, associated with the external oblique surgical treatment modalities. Clinicians with the two-wall osseous crater as the ridge. It is important to remember differed in opinion concerning the initial most common type of osseous defect. The that osseous surgery is best-suited to incisions, amount and location of bone osseous crater has been found to make up treating early and moderate periodontal removal, degree of flap elevation, and about one-third of all defects and about defects. Advanced periodontal lesions methods of suturing. The variability two-thirds of all mandibular osseous or isolated deep craters may require in postoperative maintenance regimes defects.7,8 They are twice as common in some bone contouring, but not for the further complicated the transition of posterior segments as in anterior.7,8 The express purpose of eliminating the these procedures from research to clinical greater frequency in the posterior areas defect. Selective extraction, grafting practice. This disparity fueled a healthy is probably due to the thickened alveolar procedures, and/or root amputations exchange of ideas that has improved the housing in the posterior, as well as the are often necessary to manage such modern design of clinical research and wider interproximal contact area between areas. Three-wall bony defects should helped define the periodontal surgical adjacent teeth. In the anterior region, be managed by regenerative techniques procedures now provided for patients on the slender cone of the interproximal since removal of supporting bone would a daily basis. However, this disparity also bone is gradually blunted by progressive often jeopardize the future of the affected made for great difficulty in scientifically bone resorption. Crater formation in the tooth, as well as the adjacent teeth. Other determining the superiority of one anterior occurs only after extensive bone precautions must also be taken into procedure over another. Thus was born loss. The bone between the posterior consideration before one decides to use the controversy that is still debated. teeth presents a flat occlusal surface in osseous surgery. If too much supporting Part of the controversy surrounding health. Bone destruction rapidly creates bone must be sacrificed on sound teeth osseous surgery has involved the extent an intrabony crater. To a great extent, to retain a neighboring affected tooth, of bone removal necessary for the the thickness of bone and the pattern it may be better to sacrifice the involved creation of a positive osseous architecture. of inflammation determine the pattern tooth or leave a residual bony defect. If Ochsenbein said, “The primary objective of bone loss on the lateral and medial a furcation will be exposed because of of osseous surgery is to remove the surfaces of the teeth. Thin plates of bone an extensive sacrifice of bone, it may be minimal amount of bone that will meet resorb in an apical direction without better to accept a deep gingival crevice. It the needs of an adequate architectural crater formation. Thicker ledges of should also be noted that osseous surgery form.”15 A study by Selipsky16 found that bone undergo incomplete resorption, should not be done in areas that have during osseous surgery, the average height resulting in the formation of a crater pocket depths of less than 5 mm. Shallow of supporting bone removed per tooth or well adjacent to the tooth.7-9 Reasons pockets treated with osseous surgery was only 0.6 mm. Loss of interproximal for the high frequency of interdental result in a net loss of attachment.10-14 bone support was negligible, except where

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severe angular defects were present. He also found that the majority of ostectomy performed was midbuccal, midlingual, or palatal adjacent to interproximal defects. Even on these surfaces, only about 1 mm Figure 1a. Preoperative view of the maxillary left buccal. Figure 1b. View of the maxillary left buccal after of supporting bone was removed. Selipsky osseous recontouring. also noted that removal of buccal or lingual bone seems to be less important in terms of tooth support than the removal of interproximal bone. This is because roots are generally irregular in shape, and the buccal or lingual surfaces have a smaller surface area than the flattened root form extending buccolingually. The result is that interproximal bone gives more support in terms of surface area than does buccal or lingual bone, especially in the posterior.16 It was also once believed that removal Figure 1c. Preoperative view of the maxillary left Figure 1d. View of the maxillary left palatal after palatal. osseous recontouring. of supporting bone might increase . However there is no scientific evidence to support this claim. Selipsky found that teeth initially loosened postsurgically, but returned to pre- operative mobility levels within one year. This response occurred without any form of splinting. Only time and a healthy environment were needed to obtain the reduction in mobility to presurgical levels.16 Smith and colleagues, in a study comparing osseous resection with flap Figure 2a. Preoperative view of the mandibular right Figure 2b. View of the mandibular right buccal after curettage, also confirmed these results. buccal. osseous recontouring. They found no net change in tooth mobility at six months postsurgery.14 The most complete treatise on osseous surgery to date is Ochsenbein’s “Primer for Osseous Surgery.”17 In this work, he describes in great detail the classification of molar osseous craters and the variations of molar root morphology that affect surgical decision-making. These relationships are critical to understanding the disease process, and they aid in proper surgical management of the posterior Figure 2c. Preoperative view of the mandibular right Figure 2d. View of the mandibular right lingual after lingual. osseous recontouring. regions. The dimensions of the osseous crater and the size of the molar root

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trunk give an indication as to how much periodontitis. However, the greatest As was the case with the earlier study, bone is present coronal to the level of increase in 1-3 mm probing depths was the quadrants treated with flap and the furcation. This information dictates found in the osseous surgery group. Sites osseous resection resulted in greater the limits of osteoplasty and ostectomy treated by osseous surgery also had the probing depth reduction in sites that performed in every periodontal osseous fewest sites in the 4-6 mm and 7 mm or originally demonstrated probing depths surgery. A maxillary first molar with a greater range at the one-year evaluation greater than 5 mm. All three modes of short root trunk, for example, may have period. They also found an increase in therapy produced significant and equal only 1 mm of radicular bone coronal to the clinical attachment levels for the 4-6 gains in clinical attachment levels in sites buccal furcation. Anatomic considerations mm pockets from postsurgery to one greater than or equal to 7 mm. However, such as this call for judicious management year. This increase occurred for all three shallower sites treated by root planing of the osseous crest when performing of the treatment modalities. Kerry and did show slightly better gains in clinical recontouring procedures so as not to colleagues reported on the results of this attachment levels than modified Widman invade the furcation unnecessarily. study after five years. The five-year results and osseous resection. The palatal and lingual approach were very similar with regard to probing In a companion study, Kaldahl and to osseous surgery is advocated in the depths and clinical attachment levels.12 colleagues19 evaluated the incidence of posterior regions due to the location Kaldahl and colleagues10 followed 82 breakdown sites in the above group of of the buccal furcations, the level of patients over two years. Quadrants were patients. If a site lost 3 mm or more the osseous crest, inclination of the randomly assigned to coronal scaling, of clinical attachment level from three mandibular molars, and the position root planing, Widman surgery, or osseous weeks postsurgically or post scaling of infrabony defects.15 This approach resection surgery. Initial therapy consisted and root planing, it was classified as a conserves alveolar bone on the buccal of coronal scaling in the quadrant that breakdown site. Over the course of the aspect, thereby sparing the furcations. received coronal scaling as the treatment study, the incidence of sites breaking While this technique is more time- modality. The quadrants designated for down was greater for deeper sites than consuming than others, it helps to root planing or surgery received root for shallow sites. This was true for each prevent the overzealous removal of bone planing. At the re-evaluation, additional of the treatment modalities. Sites treated on the buccal aspect and the creation of root planing was completed as needed for by osseous surgery, however, did show a negative osseous architecture (Figures 1 the quadrant receiving root planing as the the lowest incidence of breakdown when and 2). treatment. The areas assigned for surgery compared with the other treatments. This Becker and colleagues11 compared had surgery completed as planned. In the was true for pocket depths in all ranges, scaling, osseous surgery, and modified quadrants receiving osseous surgery, teeth i.e., 1-4 mm, 5-6 mm, and greater than or Widman surgery in 16 patients over one were extracted and roots amputated to equal to 7 mm. year. Each technique was carried out by facilitate pocket elimination. Surgery was In 1985, Townsend-Olsen and a periodontist who is a proponent of only performed where pocket depths of colleagues13 published a follow-up study that technique and is experienced in its 5 mm or greater were present after initial initiated by Smith and colleagues. They application. All patients were diagnosed therapy. Results of this study show that re-evaluated 12 patients with moderate as having moderate to advanced adult probing depth reduction was greater in periodontitis who underwent open flap periodontitis. Prior to surgery, each deeper pockets and greatest for osseous curettage and osseous resection surgery patient had two one-hour sessions of surgery. In 5-6 mm sites, Widman and in bilateral quadrants. Both the open oral hygiene instructions with scaling root planing resulted in a slightly greater flap curettage and osseous resection and root planing. All patients had each gain in clinical attachment levels than surgeries were completed by apically of the three procedures performed in osseous surgery, but these gains were positioning the flaps at the osseous crest. different, randomly selected quadrants. similar in pockets greater than 6 mm. Plaque control, root planing, and occlusal After one year, the results showed that Kahdahl and colleagues18 also adjustment were performed prior to the scaling, osseous surgery, and the modified reported on the seven-year follow-up surgery in all quadrants; and the patients Widman procedure were effective in of these patients. Of the original 82 were followed at six-month intervals for treating moderate to advanced adult patients, 51 were available for follow-up. the first two years. After two years, the

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patients were seen every three months osseous recontouring. This was true for the nnPermits access for correction of until the completion of the study three one-, three- and six-month examinations. radicular anomalies (e.g., cervical years later. Probing depths, clinical They also found that in those patients who enamel projections, enamel pearls, pin attachment levels, and sounding to bone received osseous recontouring, the levels perforations, etc.); were used to measure differences between of subgingival periodontal pathogens were nnFacilitates recontouring of restorative procedures at the various time points. also significantly lower at all examination overhangs; and Plaque index, gingival index, mobility, periods. nnPermits restorative crown lengthening width of keratinized tissue, and level of Periodontal osseous surgery has where indicated. the gingival margin were also measured. been shown to effectively reduce mean The advent of osseous surgery for Results after five years showed that probing depth, decrease clinical signs the treatment of early to moderate both procedures reduced probing depths of inflammation, and contribute to periodontal disease was spurred by the initially. However, the osseous surgery the overall stabilization of the clinical shortcomings of soft tissue procedures quadrants maintained these decreased attachment. According to the American such as and . probing depths to a significantly greater Academy of Periodontics parameters of These procedures were effective in extent than the flap curettage quadrants, care,21 “the goals of periodontal therapy the short-term reduction of pocket especially in the interproximal areas. are: to alter or eliminate the microbial depth and improved access for root In addition, the quadrants treated with etiology and contributing risk factors debridement, but did so at the expense osseous surgery had significantly fewer for periodontitis, thereby arresting the of the gingival width. Apical positioning sites that bled on probing. In areas that progression of the disease and preserving of the mucoperiosteal flap during initially demonstrated attachment loss, the dentition in a state of health, surgery preserves keratinized tissue there was no change from baseline in comfort, and function with appropriate while achieving a minimal posttreatment attachment levels at five years with either esthetics, and to prevent the recurrence of probing depth. Bony projections and procedure. periodontitis.” Osseous surgery is effective aberrations such as tori and ledges are Recently, Tuan and colleagues20 in achieving many of these therapeutic often encountered during flap surgery reported a study comparing the clinical and goals. When properly performed, it and require osteoplasty to achieve proper microbiological study of apically positioned achieves a physiologic architecture of the adaptation of the gingival flap. Osseous flaps with and without osseous surgery. marginal alveolar bone that is conducive surgery allows for the appropriate access They evaluated 14 adult periodontitis to gingival flap adaptation and minimal to recontour these anomalies, and patients with interproximal craters. In probing depth. The advantages of this achieve minimal sulcus depth wherever seven patients, osteoplasty and ostectomy surgical modality include the following: possible (Figure 3). This improved access were performed from the lingual/palatal nnProduces immediate and predictable is also beneficial during root resection aspect to eliminate interproximal osseous reduction in probing depth; procedures to access complete removal defects, and to mimic the original alveolar nnImproves access for daily oral hygiene of the root and allow the creation of a bony transition to the adjacent teeth. and periodic maintenance; cleansable convex surface. In another seven patients, the surgical nnPreserves gingival width via apically The difficulty in removing all causative flap was adapted to pre-existing osseous positioned flaps; agents from the radicular surface of a defects. Patients were instructed in oral nnAllows complete removal of tooth has been extensively reported in hygiene and were seen on a three-month granulomatous tissue; the periodontal literature.22-26 Although supportive periodontal therapy schedule. nnAllows visualization and access for surgical access does not guarantee Three periodontal sites having initial depths definitive debridement of radicular definitive instrumentation of the root from 4 to 8 mm were examined at baseline surfaces; surface, its effectiveness is greatly and one, three, and six months. Clinical nnPermits recontouring of bone enhanced by visualization of the field measurements and subgingival microbiota anomalies (e.g., tori, ledges); during debridement. It is not unusual were evaluated at each examination period. nnAllows appropriate access for root during osseous surgery to encounter a Results showed that pocket depths were resection and hemisection when deep fluting or narrow furcation that is reduced more in the group that received necessary; laden with calcareous deposits (Figure

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4). Osseous surgery permits access to Minimal pocket depths (less than 3 mm) these root features and allows removal of have been shown to be one-fourth as deposits and anomalies such as enamel likely as pocket depths greater than 3 projections or enamel pearls that encroach mm to show subsequent attachment upon the furcation and may exacerbate loss.27 This improved accessibility to the Figure 3a. Preoperative view of the mandibular left lingual showing large lingual tori. the progression of attachment loss. root surface to remove etiologic factors The application of osseous surgery and reduction in pocket depth are to restorative dentistry is also very consistent with the goal of preventing the significant. Today’s esthetic procedures recurrence of periodontitis after surgical demand an even greater attention to intervention. the soft tissue margin adjacent to a Although endpoints to therapy may restoration than ever before. Violation differ slightly among the periodontist, of the biologic width often detracts from restorative dentist, and patient, the the esthetics of a restoration and poses a advantages of osseous surgery are problem in capturing the impression of significant to all. The treatment of the tooth preparation. Osseous surgery periodontal disease often requires achieves a greater axial crown length the application of several procedures

Figure 3b. View of mandibular left lingual with lingual that aids in retention and creates an to obtain the intended outcome. flap elevated, showing large lingual tori. appropriate sulcus depth to conceal the Determining factors for success reside restorative margin. In the case of early to in proper clinical diagnosis, appropriate moderate periodontitis, the immediate choice and execution of therapies, and and predictable reduction in probing the realistic assessment of outcome. It depths following osseous surgery is is important to remember that osseous reassuring to the restorative dentist, surgery is but one of the several surgical especially when it concerns strategic treatment modalities that may be used abutments for a fixed partial denture. to treat periodontal disease. Other Perhaps the most notable advantage surgical modalities may be effective when of osseous surgery is the improved executed properly in the appropriate access it provides postsurgically for daily situation. The European Workshop on oral hygiene and periodic maintenance. stated that periodontal Figure 3c. View of the mandibular left lingual showing Shallower pockets are easier for both the therapy using different surgical modalities osseous recontouring and removal of tori. patient and the therapist to maintain. has been shown to be equally effective in reducing pocket probing depth, controlling the progression of chronic adult periodontitis, and achieving improved levels of probing attachment.28 It may be that the most important factor in successful periodontal therapy is not the therapeutic modality, but the posttreatment maintenance program. However, osseous surgery does remain a viable, time-tested treatment modality that offers a predictable reduction in Figures 4a and 4b. The main objective of any periodontal surgical procedure is to the gain access to the root surfaces probing depths, a decrease in gingival for more effective removal of calculus and the associated subgingival microbiota. inflammation, and a soft tissue form that is conducive to long-term maintenance.

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References 23. Hill RW, Ramford SP, et al, Four types of periodontal 1. Schluger S, Osseous resection -- a basic principle in treatment compared over two years. J Periodontol 52:655-62, periodontal surgery. Oral Surg Oral Med Oral Pathol 2:316-25, 1981. 1949. 24. Lindhe J, Westfelt E, et al, Healing following surgical/ 2. Carranza FA Sr, Tratamiento Quirurgico de la Paradentosis nonsurgical treatment of periodontal disease. J Clin (thesis). University of Buenos Aires, Argentina, 1935. Periodontol 9:115-28, 1982. 3. Proceedings of the World Workshop in Clinical Periodontics, 25. Lindhe J, Westfelt E, et al, Long-term effect of surgical/ July 23-27, 1989. nonsurgical treatment of periodontal disease. J Clin 4. Carranza FA Jr and Newman M, Clinical Periodontology, 8th Periodontol 11:448-58, 1984. ed. WB Saunders Co, 1996, pp 615-21. 26. Pihlstrom B, McHugh RB, et al, Comparison of surgical 5. Friedman N, Periodontal osseous surgery: osteoplasty and and nonsurgical treatment of periodontal disease. J Clin osteoectomy. J Periodontol 26:269, 1955. Periodontol 10:524-41, 1983. 6. Carranza FA Sr and Carranza FA Jr, Clinical Periodontology, 27. Haffajee AD, Socransky SS, et al, Relation of baseline Vol 3. WB Saunders, Ch 56, pp 615-21. microbial parameters to future periodontal attachment loss. J 7. Manson JD and Nicholson K, The distribution of bone defects Clin Periodontol 18:744-50, 1991. in . J Periodontol 45:88, 1974. 28. Wachtel HC, Surgical periodontal therapy, Proceedings of 8. Manson JD, Bone morphology and bone loss in periodontal the 1st European Workshop on Periodontology. Quintessence disease. J Clin Periodontol 3:14, 1976. Books, Chicago, 1994, pp 159-71. 9. Saari JT, Hurt WC, and Briggs NL, Periodontal bony defects on the dry skull. J Periodontol 39:278, 1968. 10. Kaldahl WB, Kalkwarf KL, et al, Evaluation of four modalities of periodontal therapy: mean probing depth, probing attachment level, and recession changes. J Periodontol 59:783-93, 1988. 11. Becker W, Becker BE, et al, A longitudinal study comparing scaling, osseous surgery, and modified Widman procedures, results after one year. J Periodontol 59:351-65, 1988. 12. Kerry GJ, Becker W, et al, Three modalities of periodontal therapy, five-year final results, Part II. J Dent Res 69(spec issue):246, 1990. 13. Townsend-Olsen C, Ammons W, and Van Belle G, A longitudinal study comparing apically repositioned flaps, with and without osseous surgery. Int J Perio Rest Dent 5(4):11-3, 1985. 14. Smith DH, Ammons WF, and Van Belle G, A longitudinal study of periodontal status comparing osseous recontouring flap with flap curettage, Part I: results after six months. J Periodontol 51:367-75, 1980. 15. Ochsenbein C, Current status of osseous surgery. J Periodontol 48:577, 1977. 16. Selipsky H, Osseous surgery -- how much need we compromise? Dent Clin N Am 20(1):79-106, January 1976. 17. Ochsenbein C, A primer for osseous surgery. Int J Periodont Restorative Dent 6(1):5, 1986. 18. Kaldahl W, Kalkwarf KL, et al, Long-term evaluation of periodontal therapy, Part I: response to four therapeutic modalities. J Periodontol 67:93-102, 1996. 19. Kaldahl WB, Kalkwarf KL, et al, Long-term evaluation of periodontal therapy, Part II: incidence of sites breaking down. J Periodontol 67:103-8, 1996. 20. Tuan MC, Nowzari H, and Slots J, Clinical and microbiological study of apically positioned flaps, with and without osseous surgery (research forum poster session). American Academy of Periodontology annual meeting, 1998. 21. American Academy of Periodontology, Parameters of Care. American Academy of Periodontology, Chicago,1996. 22. Sherman PR, Hutchens LH, and Jewson L, The effectiveness of subgingival , Part II: clinical responses related to residual calculus. J Periodontol 61:9-15, 1990.

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Periodontal Medicine: Assessment of Risk Factors for Disease

Perry R. Klokkevold, DDS, MS

abstract The approach to the diagnosis and treatment of periodontal disease is changing. The disease has not changed, but dentistry’s understanding of the pathogenesis and appreciation for the influence of host factors has improved. As a result, the approach to the management of the disease is evolving. This paper reviews some of the host risk factors that have been linked to an increased severity of periodontal disease and briefly highlights some of the evidence that has led to the current belief that periodontal disease may be a risk factor for adverse systemic health conditions.

author uring the past several decades, to achieve with such advances. More a great deal has been learned importantly, these advances in knowledge, Perry R. Klokkevold, DDS, MS, is an adjunct associate about the pathogenesis of understanding, and technology have professor and clinical periodontal disease and the not changed the routine periodontal director in the Section bacterial pathogens that are examination nor the practitioner’s ability of Periodontics at the Dresponsible. The improved understanding to identify patients at increased risk of University of California of the pathogenesis has led to the future disease. at Los Angeles School of Dentistry. development of many new diagnostic Periodontics, like many other tools and therapies. Both diagnostic and specialized areas of dentistry, is undergoing therapeutic advances have been primarily yet another change. The current era of directed at local factors (i.e., bacterial change in periodontics is focusing on plaque). Specifically, they have focused host factors. This evolution is being on identifying the bacterial pathogens stimulated by new evidence that suggests and decreasing or blocking the effects a link between systemic factors and the of their tissue-destructive enzymes. severity of periodontal disease. At the Although many new diagnostic tests have World Workshop in Periodontics in 1996, been developed, such as DNA probes for a committee appointed by the American detecting known periodontal pathogens, Academy of Periodontology to assess the they have not had the impact on diagnosis current knowledge and summarize the and therapy one might have hoped status of periodontics concluded that

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assessment of risk was an integral part specific periodontal sites) to increased studies have found that the quantity of of diagnosing and treating periodontal bacterial plaque and the risk of periodontal plaque was only weakly correlated with disease. Page and Beck reported that disease. Anatomically difficult to clean periodontitis.10-12 evidence to support risk assessment in or inaccessible areas such as deep However, it appears that the clinical decisions is substantial.1 Evidence periodontal pockets, calculus deposits, progression of periodontitis can be emerging from clinical research has shown furcation defects, defective restorations, controlled with meticulous oral hygiene that patients with systemic diseases (e.g., pontic spaces, and poor interproximal and professional cleanings (i.e., elimination diabetes) as well as patients with other contact areas can serve as harbors for the of plaque can halt the progression of systemic factors (e.g., smoking) have an undisturbed growth and maturation of periodontitis).13 Studies using qualitative increased risk and severity of periodontal bacterial plaque. These inaccessible areas measures of plaque (i.e., specific periodontal disease. As a result, these systemic “host” (especially periodontal pockets of 5 mm pathogens) have offered mixed results. factors are now being recognized as or more) are more likely to harbor and While periodontal pathogens are essential significant contributors to development promote the disproportionate growth for periodontal disease destruction, these and progression of periodontal disease. of pathogenic microorganisms because pathogenic microorganisms alone are In addition to findings that support they have decreased oxygen tension. As not sufficient to explain the differences an increased risk relationship between a result, they become sites for increased observed in periodontal disease severity. systemic disease and periodontitis, growth of anaerobic, gram-negative, Recent studies on various factors that evidence is also emerging to support putative pathogenic bacterial species. In influence disease progression indicate the idea that periodontitis may have an attempt to eliminate the pathogenic that the putative bacteria associated an adverse effect on systemic health.2-8 microorganisms, the host mounts an with periodontal disease are only slightly Specifically, periodontal disease has inflammatory response. results significant. Factors in addition to bacterial been associated with an increased risk when the tissues become inflamed. plaque must also contribute to periodontal of coronary heart disease; poor glycemic Vascularity increases, which causes edema; disease destruction. Periodontitis is now control in diabetics; respiratory disease; and tissues become erythematous. The seen as resulting from complex interplay and preterm, low-birth-weight babies. thins and bleeds easily. of bacterial infection and host response, As a result of these new findings, The inflammatory response includes the often modified by behavioral factors14 much attention is being given to the release of many cytokines, which act as (Figure 1). Perhaps the most fundamental interrelationship between periodontal chemoattractants for the recruitment change in our understanding of periodontal disease and systemic health. Periodontal of additional inflammatory cells and diseases is that not all individuals are medicine is a term that has been used to perpetuates inflammation. Some of these equally susceptible to severe disease. describe this new era in periodontics. This cytokines – most notably IL-1B, TNF-a, Some individuals are more at risk for paper reviews some of the host risk factors and PGE2 – directly contribute to gingival periodontitis than others. Several studies that have been linked to an increased connective tissue and alveolar bone have led to the current understanding severity of periodontal disease and briefly destruction. Periodontitis results when that only about 5 percent to 20 percent highlights some of the evidence that has these pathogens and the inflammatory of the population is vulnerable to severe led to the current belief that periodontal response begin to break down the periodontitis.15 disease may be a risk factor for adverse periodontal attachment. Periodontal One of the best predictors of future systemic health conditions. pocket depth increases and alveolar bone disease progression appears to be past resorbs. disease.15 An individual who has suffered Local Risk Factors for Periodontal There is little debate about the fact from periodontitis previously is more Disease that periodontal pathogens contribute to likely to experience future disease There is ample evidence to demonstrate the pathogenesis of periodontal disease. destruction than an individual who has a relationship between bacterial plaque However, the evidence to support a not had previous disease. On the one and gingival inflammation.9 Poor relationship between bacterial plaque and hand, an individual with increased pocket compliance with oral hygiene and other the progression of periodontitis is limited. depth (past disease) is more likely to local factors expose individuals (and Results from well-controlled clinical experience further disease destruction

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because the increased pocket depth is more likely to harbor and promote the growth of pathogenic bacteria. However, the other possibility is that systemic or environmental factors that originally predisposed that individual to periodontitis may continue to predispose him or her to future disease. Hence, the existence of previous disease is a positive indicator for that individual’s “risk” of future disease. This latter view suggests a significant role of the host in the development and progression of periodontitis. Host factors that may have more influence on disease progression than periodontal pathogens include diabetes, smoking, stress, and genetic predisposition. Thus, it has become essential to identify systemic “host” factors that increase the risk of periodontal disease destruction.

Systemic ‘Host’ Risk Factors Figure 1. Over the past several decades, our understanding of periodontitis has evolved from a simplistic model to a more complex interplay between bacterial infection and host response. In the simple model (top) we assumed that pathogenic Diabetes Mellitus bacteria were responsible for periodontitis and all individuals were equially Diabetes is a systemic condition susceptible to disease. The current more complex model (bottom) maintains that has long been associated with an a bacterial pathogenic etiology by also takes into consideration difference in increased risk and severity of periodontal individual susceptibility as well as environmental and host response influences. disease. The reasons for this relationship are many and relate to the pathogenesis and control of diabetes. Diabetes than diabetics with better metabolic and nondiabetics.16 Some specific mellitus is a disorder that results in poor control of their disease. mechanisms that have been proposed to metabolic control of glucose levels in the The mechanism(s) responsible for contribute to periodontitis in diabetics blood. The hyperglycemia that results increasing the risk in diabetics is unclear include polymorphonuclear neutrophil from poor control secondarily creates but is likely to be related to an increased leukocyte dysfunction, abnormal collagen systemic changes that are commonly susceptibility to infections, an impaired metabolism, and genetic predisposition.17,18 associated with the disease. Specifically, immune response, poor wound healing, While the mechanism that exacerbates poor glucose control in diabetics results or a combination of these factors. An periodontitis in diabetics is not well- in complications such as retinopathy altered periodontal microflora has also understood, the increased risk has been (blindness), atherosclerosis (cardiovascular been suggested as a possible cause for well-documented; and periodontitis can disease), poor wound healing, infections, the increased periodontal disease seen be considered a complication of diabetes, and nephropathy. Both Type I (insulin- in diabetics. However, a study of the especially in the poorly controlled. dependent) and Type II (noninsulin- quantitative and qualitative aspects Page and Beck reported that diabetics dependent) diabetes are risk factors for of the microflora (i.e., the periodontal experience about a 2.8 to 3.4 times greater periodontitis. Those with poorer control pathogens) in both Type I and Type II risk of developing destructive periodontitis have greater periodontal attachment loss diabetics revealed no significant trends as compared to nondiabetics in an adult and bone loss and progress more rapidly nor differences between diabetics population.1

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In many diabetic patients, especially the periodontal tissues may contribute Smoking and Tobacco those who are poorly controlled, the to periodontitis by changing the Smoking has long been associated with accumulation of glycosylated proteins microvasculature, impairing membrane adverse systemic health effects such as and lipids increases as compared to well- transport, and reducing the immune respiratory disease and cancer. An analysis controlled diabetics and nondiabetics. response as stated above. It has been of data from the 1971-75 National Health The glycosylation of proteins is a suggested that advanced glycosylated and Nutritional Examination Survey in the normal nonenzymatic occurence for all end products induce an oxidant stress United States showed a clear relationship individuals, but it is significantly increased in the gingival vasculature that may be between smoking and periodontitis.24 in those with hyperglycemia. The change responsible for the accelerated injury Many studies since then have provided permanently alters the structure of the and impaired healing seen in diabetics.20 strong evidence to support an increased protein and can be detected by laboratory The accumulation of the end products risk relationship between smoking assay. This is the basis for the latest and may also make diabetics more suseptible and periodontal disease severity. In a most accurate blood screening for diabetes to periodontitis by altering the collagen comprehensive review, Salvi and colleagues – the glycosylated hemoglobin test. It is an structure and function. In the case reported that the increased risk for accurate diagnostic test used to measure of collagen glycosylation, it increases periodontitis in smokers was 2.5 to seven how well-controlled a diabetic patient has cross-linking and results in diminished times greater than that of nonsmokers.25 been during the previous two to three turnover.21 The normal repair and Proposed mechanisms include an months, which is equivalent to the half-life replacement of collagen in the periodontal altered immune response, decreased of a red blood cell (hemoglobin molecule). tissues becomes impaired and more vascularity, impaired polymorphonuclear The accumulation of advanced vulnerable to damage. neutrophil leukocyte chemotaxis and glycosylated end products in the tissues of Well-controlled diabetics with good phagocytosis, and decreased antibody diabetics alters the integrity and function oral hygiene do not show an increased production. Smoking also appears to of the affected tissues. This may be part risk of developing severe periodontitis. decrease local oxygen levels. It has been of the underlying mechanism responsible In fact, well-controlled diabetics have suggested that the resulting decreased for some or all of the complications fewer systemic complications than poorly oxygen tension may encourage growth observed in diabetics. In poorly controlled controlled diabetics and have been shown of anaerobic pathogens. However, diabetics, the vessel walls show increased to respond well to periodontal therapy.22 experimental studies have shown basement membrane thickness due to an Perhaps more importantly with respect that there is no difference between accumulation of advanced glycosylated to systemic health, periodontal therapy smokers and nonsmokers in the amount end products. In the vessel wall, these has been shown to improve the ability of plaque accumulation nor in the changes narrow the lumen and interfere of patients to metabolically control their prevalence of periodontal pathogenic with transport across to the connective diabetes.23 They can more easily maintain microorganisms.26-28 On the other tissues. These advanced glycosylated normal blood sugar levels and, thus, hand, Grossi and colleagues found that end-product related changes on the vessel require less insulin. There appears to be significantly fewer smokers became walls are responsible for the microvascular significant advantages for diabetic patients negative for periodontal pathogens complications of diabetes such as to be well-controlled and maintain good (P. gingivalis and B. forsythus) than retinopathy, atherosclerosis, poor wound periodontal health. For this reason, nonsmokers.22 This is consistent with a healing, infections, and nephropathy. In awareness, improved diagnosis, and better report by Zambon and colleagues that turn, advanced glycosylated end products communication between dentists and smoking increases the risk for subgingival may be related to the increased incidence physicians have the potential to enhance infection.29 The periodontal pathogens and severity of periodontal disease the prognosis and therapy for diabetic are re-established in the periodontal observed in diabetics. patients. Coordinating the periodontal and pockets of smokers much more rapidly The effect of advanced glycolsylated medical management of diabetes benefits than in nonsmokers following periodontal end products on periodontal disease the patient by improving the control of therapy. This finding is also consistent with associated with diabetes is being studied.19 hyperglycemia and enhancing the response previous reports in that the periodontal The accumulation of the end products in to periodontal therapy. pathogens are the same and may account

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for the poorer response to periodontal increased vasoconstriction, an impaired paradoxical findings in smokers, that is, therapy seen in smokers. immune response, or a combination of less gingival inflammation and less gingival Bacterial plaque (periodontal these factors. Smoking suppresses the bleeding associated with more periodontal pathogens) may not be the major vascular reaction normally observed with destruction as compared to observations in contributor to bone loss in the periodontal gingivitis and periodontitis.32,33 This may nonsmokers. destruction seen in smokers. To appreciate be due to decreased vascularity (fewer In addition to an increased prevalence the effect of smoking on alveolar bone, new vessels and/or vasoconstriction) and severity of periodontal disease, Bergstrom and Eliasson evaluated 235 in the gingiva of smokers. There are smokers have a decreased capacity to dental hygienists (a group thought to have mixed reports about whether nicotine respond to surgical therapy. The healing very good oral hygiene habits).30 Seventy- causes vasoconstriction or vasodilation response following periodontal therapy is two were smokers. Alveolar bone height in gingival tissues. In central tissues decreased as compared to nonsmokers.36 was significantly reduced in smokers as such as heart muscle, nicotine causes However, individuals who quit smoking compared to nonsmokers. The degree of vasodilation, whereas in peripheral recover with a healing response that is bone loss increased with years smoking tissues such as the skin, nicotine causes comparable to nonsmokers.36 Smoking and amount smoked. Presumably in this vasoconstriction. Some reports suggest cessation has been shown to have dental-hygiene-educated population, that nicotine causes vasoconstriction of beneficial effects on the periodontal tissues bacterial plaque did not play a contributory gingival tissues. However, Baab and Oberg, and the response to periodontal therapy.37 role in bone loss. Only 2 percent had using a microdoppler (flux = velocity x The decreased capacity of smokers to light calculus. The amount of smoking in number cells), found that nicotine caused respond well to surgical therapy appears pack years is important to assess when an increase in gingival blood flow.34 It is to be true for implant therapy as well.38 determining an individual’s risk for possible that an increase in heart rate Although the findings suggest that a periodontitis. may have contributed to this finding by perioperative smoking cessation program Refractory periodontitis is increasing the velocity. would improve implant success rates, it characterized by low levels of plaque and In addition to the vascular effects, is important to note that the number of a poor healing response to periodontal nicotine causes a decreased immune patients and duration of study are limited. therapy. MacFarlane and colleagues response. Both oral and peripheral More studies are needed to evaluate the evaluated a group of 31 patients with neutrophils are effected by nicotine. benefits of a short-term smoking cessation refractory periodontitis and found that They have decreased chemotactic program. there were no chemotactic defects, but response to antigen and decreased phagocytosis was significantly impaired.31 phagocytic ability. The immune system Psychosocial Stress Interestingly, they retrospectively in smokers is decreased via impairing Psychosocial stress has been associated discovered that a vast majority (28 of 31) polymorphonuclear neutrophil leukocyte with periodontal disease. In World War II, of the refractory disease patients were phagocytosis and decreasing antibody soldiers on the battlefield presented with smokers. The unusually high number of levels. The antibody production, specifically trench mouth, a condition also known smokers (more than 90 percent) found in IgG and IgA, is suppressed in smokers.25 as acute necrotizing ulcerative gingivitis. this group as compared to the percentage Nicotine plays a role in periodontal This form of periodontal disease is known of smokers in Minnesota’s general destruction by up-regulating cytokine to be stress-related.39 The mechanism population (21 percent) appears to strongly production. Payne and colleagues showed of stress-induced periodontal disease implicate smoking as a major risk factor for increased production of prostaglandin destruction is not well-defined. However, refractory periodontal disease. (PGE2) and cytokine (IL-1fl) in it has been known for many years that In some smokers, the appearance of response to nicotine.35 These immune increases in corticosteroids, whether the gingiva does not reflect the severity regulatory mediators are known to exogenous or endogenous, decrease the of the inflammation nor the degree increase periodontal destruction. The immune response. Psychosocial stress may of periodontal destruction. This lack vasoconstrictive activity of nicotine along predispose a susceptible host by decreasing of inflammation in the gingiva may with the destructive effects of immune the immune response to pathogenic be explained by decreased vascularity, system up-regulation may explain the bacteria and altering wound healing.

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Genco and colleagues are studying polymorphisms of the IL-1 genotype and the various aspects of psychosocial stress the expressed phenotype of severe adult Traditionally, the complete periodontal such as type, duration, and the patient’s periodontitis. Subsequently, the first examination consisted of evaluating and ability to cope as it relates to periodontal commercial genetic test for susceptibility documenting several findings (signs and disease.40 They believe that psychosocial to periodontitis became available (PST, symptoms of disease). It typically includes stress without the ability to cope may be Medical Science Systems, Flagstaff, Ariz.). an evaluation and charting of probing more detrimental than similar stresses The degree of increased risk of severe pocket depth, attachment loss, gingival experienced by individuals with good periodontitis for genotype-positive margins, inflammation, bleeding on coping mechanisms. patients is estimated to be about 6.8 probing, sulcular exudate, missing teeth, The role of stress in aggravating times greater as compared to genotype- contacts, and occlusion. These findings systemic conditions (e.g., cardiovascular negative individuals. It is estimated that are used to detect or diagnose existing disease) has been well-documented. approximately 30 percent of the population periodontal disease. In practice, re- However, the evidence to support a may be positive for this genetic marker. evaluations are used to “monitor” patients relationship between psychosocial stress No previous studies have shown a genetic and to alter the course of their treatment and periodontal disease is limited. In a relationship for chronic severe adult based on clinical findings. Unfortunately, case-controlled analysis of psychosocial periodontitis. It is interesting to note that these clinical findings do not provide factors and adult periodontitis, Moss and this relationship was only appreciated any prognostic information. Even those colleagues showed that individuals testing when smokers were removed from the findings thought to be predictive of positive for antibody to the periodontal data analysis. The effect of smoking on future periodontal disease breakdown, pathogen B. forsythus and rating high periodontitis had such a strong negative such as and poor on the depression scale were 5.3 times impact that it outweighed the effects of oral hygiene, have failed to correlate with more likely to have periodontitis than genetic predisposition. future disease activity.44 Only purulence, a individuals testing negative for B. forsythus An important distinction between relatively rare finding, has been associated antibody and depression.41 Although these genotype-positive individuals and patients with periodontal disease progression.45 findings are suggestive, it is too early to with existing periodontal disease is that Conversely, lack of bleeding on probing make conclusive statements about the individuals who are genotype-positive and good oral hygiene are consistent with relationship of stress and periodontal do not necessarily have the disease. It periodontal health.13,46 disease destruction. is possible that these individuals have An example of the poor prognostic a genetic predisposition for severe ability of traditional clinical parameters was Genetic Predisposition periodontitis, but they have not yet been reported by McGuire and Nunn.47,48 They Genetics or familial inheritance challenged by periodontal pathogens and classified each tooth into prognostic groups of periodontal disease has long been they do not have signs of periodontitis. based on clinical findings at baseline and suspected but difficult to prove. With Theoretically, if these genotype-positive five and eight years later. Following 12 their study of adult twins and periodontal patients are not challenged by periodontal years, patients were examined and the disease, Michalowicz and colleagues pathogens, they may remain periodontally prognostic values were compared to actual were the first to demonstrate that, healthy. Once identified, these patients tooth retention. Except for those teeth indeed, periodontal disease was linked (as well as other patients with known given a good prognosis, the predictive value to genetics.42 Several studies have risk factors) may be able to be placed into of these findings (with an experienced subsequently shown a similar relationship high-risk preventive programs to prevent or periodontist) was poor. Teeth given a good between juvenile periodontitis and genetic reduce the future incidence of disease, that prognosis were retained and continued predisposition. In 1997, Kornman and is, if an individual is known to be susceptible to have a good prognosis. However, those colleagues published the first evidence of (genotype-positive, diabetic, smoker, etc.), teeth given a less than good (i.e., fair, poor, a specific genetic marker for susceptibility then every effort should be made to prevent questionable, hopeless) prognosis were to severe chronic adult periodontitis.43 the exposure to the periodontal pathogens often incorrectly predicted. The accuracy The basis of that work was the discovery (i.e., excellent oral hygiene and prevention of prognostic factors following five years of a relationship between specific via a frequent recall program). was 43 percent. The accuracy fell to 35

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percent following eight years. Based on this coronary heart disease than those without changed, but dentistry’s understanding of study, the ability to predict tooth retention periodontitis.7 The risk was especially high the pathogenesis and appreciation for the using traditional clinical parameters was for men under age 50 (1.7 times greater). influence of host factors has improved. As less than 50 percent. Recognizing that This analysis also found that periodontitis a result, the approach to the management this is only one study and that teeth are and poor oral hygiene were more strongly of the disease is evolving. This article sometimes extracted for reasons other associated with total mortality th an has highlighted some of the emerging than periodontal disease, the findings with coronary heart disease, which could evidence that links periodontal disease suggest that prognosis requires more that indicate that neglect of oral health is more and systemic health. There is a rapidly just an evaluation of traditional clinical an indicator of poor health habits than an growing body of data that supports a parameters. etiologic factor. periodontal medicine interrelationship. This method of examination and The mechanism(s) for the relationship Current evidence suggests that systemic documentation remains an important between periodontitis and the systemic factors contribute to the severity of part of identification, prevention, and effects it may have are beginning to be periodontitis, and periodontitis may be treatment of patients with periodontitis. understood. As an example, Beck and a risk factor for systemic diseases. As However, the problem with this method colleagues suggest that periodontitis, once part of a comprehensive examination of of diagnosing periodontal disease is that established, represents a biologic burden patients for periodontal disease, dental it is limited to detecting disease after of endotoxin and inflammatory cytokines practitioners must act more like physicians it has occurred, and it assumes that all that serves to initiate and exacerbate to evaluate systemic illnesses and other individuals are equally susceptible. It does atherosclerotic and thrombogenic events.6 conditions that may contribute to the not have any predictive value nor does it Herzberg and Meyers’ study on the effects risk and severity of periodontal disease. take into consideration differences among of oral flora on platelets supports this Conversely, physicians must understand individual patients (i.e., host factors). To hypothesis.2 They found that S. sauguis the role of periodontitis in the health of identify the patients early (ideally prior induced platelets to aggregate, and they their patients and become aware of the to the onset of severe periodontitis), propose a hypothesis that they may signs of severe periodontitis. This is the practitioners must place an emphasis on cause coronary thrombosis. Additional beginning of a new era in periodontics and determining risk factors for each individual hypotheses are being studied to evaluate provides an opportunity for dentists to via better medical history (diabetes), the effect of periodontitis on respiratory develop new relationships with physician family history (genetic predisposition), diseases and the incidence of preterm, low- colleagues. Dentists should be encouraged and social history (smoking), as well as an birth-weight babies.3,5 Interested readers are to communicate with physicians about the evaluation of other environmental factors referred to a comprehensive report from health of their patients, and physicians (stress). Furthermore, since patients may the 1997 Sunstar-Chapel Hill Symposium should be alerted to the possible risks of present without knowledge of their own on Periodontal Disease and Human Health severe periodontitis. medical condition (50 percent of diabetics published in the Annals of Periodontology.8 are undiagnosed), dentists must consider It is interesting to note and important References 1. Page RC and Beck JD, Risk assessment for periodontal referral to a physician when severe disease to remember that these hypotheses are diseases. Int Dent J 47:61-87, 1997. or poor response to therapy cannot be reminiscent of the focal infection theories 2. Herzberg M and Meyer M, Effects of oral flora on explained by known factors. that fell out of favor in the 1950s and ‘60s platelets: possible consequences in cardiovascular disease. J Periodontol 67(10-supplement):1138-42, 1996. because of a lack of evidence. The link 3. Offenbacher S, Katz V, et al, Periodontal infection as a Periodontal Disease as a Risk Factor between periodontitis and systemic disease possible risk factor for preterm low birth weight. J Periodontol for Systemic Disease requires further study with well-controlled 67(10-supplement):1103-13, 1996. 4. Taylor GW, Burt BA, et al, Severe periodontitis and risk for One study analyzed data from the clinical trials. poor glycemic control in patients with non-insulin-dependent 1971-75 National Health and Nutritional diabetes mellitus. J Periodontol 67(10-supplement):1085-93, Examination Survey and correlated it with Conclusion 1996. 5. Scannapieco FA and Mylotte JM, Relationships between cardiovascular data. The report concluded Once again, the approach to the periodontal disease and bacterial pneumonia. J Periodontol that people with periodontitis at baseline diagnosis and treatment of periodontal 67(10-supplement):1114-22, 1996. had a 25 percent greater risk of subsequent disease is changing. The disease has not 6. Beck J, Garcia R, et al, Periodontal disease and cardiovascular disease. J Periodontol

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67(10-supplement):1123-37, 1996. Clin Periodontol 19:667-71, 1992. accurately predicting tooth survival. J Periodontol 67:666-74, 7. DeStefano F, Anda RF, et al, Dental disease and risk of 28. Stoltenberg JL, Osborn JB, and Pihlstrom BL, Association 1996. coronary heart disease and mortality. Br Med J 306:688-91, between cigarette smoking, bacterial pathogens, and To request a printed copy of this article, please contact: Perry 1993. periodontal status. J Periodontol 64:1225-30, 1993. R. Klokkevold, DDS, MS, UCLA School of Dentistry, Section 8. 1997 Sunstar-Chapel Hill Symposium on Periodontal 29. Zambon JJ, Grossi SG, et al, Cigarette smoking increases of Periodontics, 63-022A CHS - Dental, Los Angeles, CA Diseases and Human Health, New directions in periodontal the risk for subgingival infection with periodontal pathogens. J 90095-1668. medicine. Ann Periodontol 3(1), 1998. Periodontol 67(10-supplement):1050-4, 1996. 9. Staum JW, Epidemiology of gingivitis. J Clin Periodontol 30. Bergstrom J and Eliasson S, Cigarette smoking and alveolar 13:360-70, 1986. bone height in subjects with a high standard of oral hygiene. J 10. Haffajee AD, Socransky SS, et al, Clinical, microbiological Clin Periodontol 14:466-9, 1987. and immunological features of subjects with destructive 31. MacFarlane GD, Herzberg MC, et al, Refractory periodontal diseases. J Clin Periodontol 15:240-6, 1988. periodontitis associated with abnormal polymorphonuclear 11. Grossi SG, Genco RJ, and Machtei EE, Assessment of risk leukocyte phagocytosis and cigarette smoking. J Periodontol for periodontal disease, II: risk indicators for alveolar bone 63:908-13, 1992. loss. J Periodontol 66:23-9, 1995. 32. Bergstrom J, Persson L, and Preber H, Influence of 12. Grossi SG, Zambon JJ, and Ho AW, Assessment of risk cigarette smoking on vascular reaction during experimental for periodontal disease, I: indicators for attachment loss. J gingivitis. Scand J Dent Res 96:34-9, 1988. Periodontol 65:260-7, 1994. 33. Bergstrom J and Preber H, Tobacco use as a risk factor. J 13. Axelsson P, Lindhe J, and Nystrom B, On the prevention Periodontol 65:545-50, 1994. of caries and periodontal disease, results of a 15-year 34. Baab DA and Oberg PA, The effect of cigarette smoking longitudinal study in adults. J Clin Periodontol 18:182-9, 1991. on gingival blood flow in humans. J Clin Periodontol 14:418-24, 14. Wolff L, Dahlen G, and Aeppli D, Bacteria as risk markers for 1987. periodontitis. J Periodontol 65:498-510, 1994. 35. Payne JB, Johnson GK, et al, Nicotine effects PGE2 and IL-1ß 15. American Academy of Periodontology Research, Science release by LPS-treated human monocytes. J Periodont Res and Therapy Committee, Epidemiology of periodontal 31:99-104, 1996. diseases: position paper. J Periodontol 67(9):935-45, 1996. 36. Kaldahl WB, Johnson GK, et al, Levels of cigarette 16. Tervonen T, Oliver RC, et al, Prevalence of periodontal consumption and response to periodontal therapy. J pathogens with varying metabolic control of diabetes mellitus. Periodontol 67:675-81, 1996. J Clin Periodontol 21:375-9, 1994. 37. Haber J, Smoking is a major risk factor for periodontitis. 17. Oliver RC and Tervonen T, Diabetes -- a risk factor for Curr Opin Periodontol 23:289-92, 1994. periodontitis in adults? J Periodontol 65:530-8, 1994. 38. Bain CA, Smoking and implant failure. Int J Oral Maxillofac 18. Cutler CW, Eke P, et al, Defective neutrophil function in an Implants 11:756-9, 1996. insulin-dependent diabetes mellitus patient, a case report. J 39. Murayama Y, Kurihara H, et al, Acute necrotizing ulcerative Periodontol 62:394-401, 1991. gingivitis: risk factors involving host defense mechanisms. 19. Lalla E, Lamster IB, et al, A murine model of accelerated Periodontol 2000 6:116-24, 1994. periodontal disease in diabetics. J Periodontol Res 33(7):387- 40. Genco RJ, Ho AW, et al, Models to evaluate the role of 99, 1998. stress in periodontal disease. Ann Periodontol 3(1):288-302, 20. Schmidt AM, Weidman E, et al, Advanced glycation end 1998. products (AGEs) induce oxidant stress in the gingiva: a 41. Moss ME, Beck JD, et al, Exploratory case-controlled potential mechanism underlying accelerated periodontal analysis of psychosocial factors and adult periodontitis. J disease associated with diabetes. J Periodont Res 31:508-15, Periodontol 67(10-Supplement):1060-9, 1996. 1996. 42. Michalowicz BS, Aeppli D, et al, Periodontal findings in 21. Monnier VM, Glomb M, et al, The mechanism of collagen adult twins. J Periodontol 62:293-9, 1991. cross-linking in diabetes. Diabetes 45(Suppl 3):S67-S72, 1996. 43. Kornman KS, Crane A, et al, The interleukin-1 genotype as a 22. Grossi S, Skrepcinski F, et al, Response to periodontal severity factor in adult periodontal disease. J Clin Periodontol therapy in diabetics and smokers. J Periodontol 24:72-7, 1997. 67(10-supplement):1094-102, 1996. 44. Haffajee AD, Socransky SS, and Goodson JM, Clinical 23. Aldridge JP, Lester V, and Watts TLP, Single-blind studies parameters as predictors of destructive periodontal disease of the effects of improved periodontal health on metabolic activity. J Clin Periodontol 10:257-65, 1983. control in Type 2 diabetes mellitus. J Periodontol 67:166-76, 45. Armitage GC, Jeffcoat MK, et al, Longitudinal evaluation 1996. of elastase as a marker for the progression of periodontitis. J 24. Ismail AI, Burt BA, and Eklund SA, Epidemiologic patterns Periodontol 65(2):120-8, 1994. of smoking and periodontal disease in the United States. J Am 46. Lang NP, Adler R, et al, Absence of bleeding on probing: an Dent Assoc 106:617-21, 1983. indicator of periodontal stability. J Periodontol 17:714-21, 1990. 25. Salvi GE, Lawrence HP, et al, Influence of risk factors on the 47. McGuire MK and Nunn ME, Prognosis versus actual pathogenesis of periodontitis. Periodontol 2000 14:173-201, outcome, II: the effectiveness of clinical parameters in 1997. developing an accurate prognosis. J Periodontol 67:658-65, 26. Haber J, Wattles J, et al, Evidence for cigarette smoking as 1996. a major risk factor for periodontitis. J Periodontol 64:16-23, 48. McGuire MK and Nunn ME, Prognosis versus actual 1993. outcome, III: the effectiveness of clinical parameters in 27. Preber H, Bergstrom J, and Linder LE, Occurrence of periodontopathogens in smoker and non-smoker patients. J

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Crown Lengthening Surgery: A Restorative Driven Periodontal Procedure

David F. Levine, DDS, Mark Handelsman, DDS, and Nicolas A. Ravon, DDS

abstract Improper management of the periodontal tissues during restorative procedures is a common, but often overlooked, cause of failure. When a restoration is placed, the preservation of an intact, healthy periodontium is necessary to maintain the tooth or teeth being restored. Predictable long-term restorative success requires a combination of restorative principles with the correct management of the periodontal tissues.

authors he replacement of form, success requires a combination of restorative function, and esthetics is the principles with the correct management of David F. Levine, DDS, Mark Handelsman, DDS, is an assistant clinical is an assistant clinical primary goal of restorative the periodontal tissues. One factor that is professor at the University professor at the USC dentistry. Equally important of particular importance is the potentially of Southern California School of Dentistry. He is doing no harm when damaging result to the periodontium when School of Dentistry. He maintains a private practice Trestorations are placed. Improper margins are placed below the gingival also maintains a private in Beverly Hills. management of the periodontal tissues margin. To avoid these potential problems practice in Toluca Lake, Nicolas A. Ravon, DDS, is Calif. a clinical instructor for the during restorative procedures is a to the supporting structures of the teeth, ISP Program at USC School common, but often overlooked, cause clinical crown lengthening can provide of Dentistry. He maintains of failure. When a restoration is placed, adequate clinical tooth structure to enable a private practice in Garden the preservation of an intact, healthy the placement of margins either coronal to Grove, Calif. periodontium is necessary to maintain or at the gingival margin. the tooth or teeth being restored. The restorative dentist must attempt to Anatomy of the Gingival Complex eliminate all factors that could lead to Clinical doctrines and common the accumulation of bacterial plaque and myths regarding the gingival response to its subsequent effects on the gingival restorative materials and the limitations tissues, root surfaces, and underlying of intracrevicular tooth preparation make alveolar bone. it difficult to place restorative margins Predictable long-term restorative subgingivally. Because tissue components

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cannot be visualized, the guidelines of found that the average histologic Violations of Biologic Width sulcus depth are often misunderstood dimension of the connective tissue fibers Several studies have shown that and clinically mismanaged. Therefore, was 1.07 mm, the average histologic the position of the crown margin in before discussing crown lengthening, it dimension of the epithelial attachment relation to the gingiva can significantly is important to review the anatomy of was 0.97 mm, and the average histologic affect the gingival index, as well as the supra-alveolar tissues of the healthy dimension of the sulcus was 0.69 the pocket depth and the position of periodontium and the relevance of these mm. The combined dimension of the the epithelial attachment.6-10 It was dimensions to the position of restoration junctional epithelium and connective shown that crown margins positioned margins. tissue attachments is referred to as subgingivally were associated with the The supra-alveolar tissues include the “biologic width”2 Subsequent most gingival inflammation, whereas the and the gingival authors3,4 have also shown that a definite supragingivally located crown margins attachment. The gingival attachment joins dimensional relationship exists among were associated with the least gingival the gingiva to the tooth and is made up the alveolar crest, the supra-alveolar inflammation.6,9-10 Valderhaug7,8 showed of the connective tissue attachment and connective tissue attachment, the that loss of periodontal attachment was the epithelial attachment. The gingival junctional epithelium, and the base of significantly higher around teeth with attachment is made up of connective the gingival sulcus. subgingivally located crown margins than tissue fibers that are embedded in Understanding and clinically around similar teeth with crown margins cementum. The epithelial attachment is managing the concept of biological located supragingivally. Furthermore, an adhesion of epithelial cells through width and the level of the osseous crest subgingivally prepared teeth exhibited hemidesmosomes. is key to maintaining periodontal health deeper pockets than teeth prepared with The concept of a minimum dimension in the presence of dental restorations. the margin at the height of the gingiva of tissue from the alveolar crest to the The location of a restorative margin or supragingivally. The same study also bottom of the gingival sulcus is based on relative to the crest of the alveolar bone showed that after five years, 30 percent of a study by Garguilo and colleagues.1 They is more critical for preserving gingival the subgingivally located crown margins examined 30 cadavers with clinically health than its distance below the free were associated with . healthy periodontia and reported on gingival margin.5 The restorative dentist There are also reports in the the average histologic dimensions of must be able to determine the height periodontal literature that claim that the connective tissue attachment, the of the osseous crest and width of the in the presence of inflammation, epithelial attachment, and the gingival gingival attachment before placing restorations that impinge upon the sulcus. They found that there appears to intracrevicular margins. This is done to gingival attachment or biologic width be a proportional relationship between prevent impingement of the soft tissue will trap bacterial plaque, induce the crest of the alveolar bone, the attachment, otherwise referred to as inflammation, and increase the severity connective tissue attachment, and the violation of the biologic width. of periodontal breakdown3-5,11-14 (Figure epithelial attachment. The investigators 2). Maynard and Wilson3 reported that

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violation of the biologic width will occurred when the plaque front was less lead to a progressive inflammation than 1.2 mm from the apical border of the with downgrowth of the epithelial junctional epithelium and that there was attachment and loss of connective no loss of bone when the plaque front was 13 tissue attachment. Allen reports that greater than 2.7 mm coronal to the bone. Figure 2a. Chronic gingival inflammation around wherever the biologic width is violated, It has been claimed that the rationale anterior crowns. there is a reaction by the periodontium. for obtaining 3 mm of distance from Alveolar bone will resorb inconsistently the expected restorative margin to the in an attempt to provide space for a new alveolar bone should not be to allow for connective tissue attachment, which will the gingival attachment and sulcus, but result in an increase in probing depth. instead to position the restorative margin, Re-establishment of the periodontal with its anticipated plaque deposit, attachment at a more apical position beyond the 2.7 mm danger zone from the and a deepened sulcus, combined with bone.19 a deep subgingival restorative margin, Regardless of the etiology of the frequently lead to chronic inflammation inflammation and bone loss, to ensure and localized periodontal breakdown. This periodontal health in the presence of is especially applicable in periodontally subgingival restorations, there must Figure 2b. Elevation of a flap shows crown margins susceptible patients. be a minimum amount of sound tooth in close proximity to alveolar crest and violation of gingival attachment or “biologic width”. It is possible that the gingival structure coronal to the alveolar crest. inflammation associated with restorations Most authors3-5,12 recommend that when that impinge on the gingival attachment supragingival margins are not feasible, is not from a physical insult, but from restorative margins should be placed at a bacterial insult. Crown margins are least 3 mm from the alveolar crest. This inherently imperfect and will eventually dimension allows a distance of 1 mm collect bacterial plaque. The average for each part of the gingival attachment marginal fit of gold restorations is 57 (connective tissue attachment and m and ceramic restorations is 48 m.15 epithelial attachment), for a total of 2 Christensen16 has stated that all cast mm. The additional 1 mm is for a healthy restorations have cement lines and that gingival sulcus. Other authors have most studies show these lines to be at recommended 4 mm or even 5 mm for the Figure 2c. New restorations after surgery to re- least 20 to 40 m thick. Since the size of a working dimension of biologic width.20,21 establish room for gingival attachment. typical microorganism is only about 1 m However, these authors take into thick, it can be assumed that most crown consideration an additional 1 to 2 mm of margins will eventually harbor bacterial tooth structure for a restorative margin. located at the cementoenamel junction. In plaque. Several studies have shown that It is also important to remember that what is termed a “high crest,” the alveolar subgingival crown margins interfere with the above guidelines are averages. Each crest is at the cementoenamel junction, gingival health.6-10 clinical situation varies and should be resulting in a minimal connective tissue Waerhaug17 claimed that the examined prior to margin placement. attachment and what is often called inflammatory lesion radiates 1 to 2 Another factor to take into “delayed passive eruption.” A “low crest” mm from the plaque front. Therefore, consideration is the relationship of the is when the osseous crest is more than it is probable that a 1 to 2 mm zone of position of the biologic width relative 2 to 3 mm apical to the cementoenamel inflammation is going to be contiguous to the cementoenamel junction. In the junction. This most often results in a long with a subgingival restorative margin. normal crestal to soft tissue relationship, junctional epithelial attachment, with the Waerhaug18 also stated that the loss of the junction of the connective tissue junction of the epithelial attachment and connective tissue attachment rarely fibers and the epithelial attachment is connective tissue fibers on cementum.

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Figure 3a. Radiographs of maillary left showing decay Figure 3b. Buccal view of maxillary left showing Figure 3c. Palatal view of maxillary left showing short under existing restorations Nos. 12 and 13 and supra-eruption subgingival margins and soft tissue cratering. clinical crowns and extent of subgingival decay removal. No. 14.

Figure 3d. Buccal view of maxillary left pre-osseous Figure 3e. Buccal view of maxillary left post-osseous Figure 3f. Palatal view of maxillary left pre-osseous resection. resection. resection.

Ochsenbein and Ross22 further defined to the scallop of the interproximal alveolar Indications tissue types as either flat or scalloped. bone. The gingival scallop is always Indications for surgical crown A scalloped architecture will have a low equal to or greater than the underlying lengthening are periodontal, restorative, crest and is usually found with a thin osseous scallop, which is greatest in the and esthetic. Periodontal considerations periodontium, causing a tendency for anterior teeth and flattens out posteriorly. include cases of “delayed passive eruption” soft tissue recession. A flat architecture Furthermore, it is important to remember and where intracrevicular placement of is usually found in patients with thicker that the osseous crest parallels the the restorative margin encroaches on tissue. Only by sounding to bone under cementoenamel junction circumferentially the gingival attachment and may lead local anesthesia can these relationships be and that the biological width follows the to inflammatory periodontal disease. determined. shape of the osseous crest. Restorative considerations include lack Measurements should be made from of retention due to short clinical crowns; the free gingival margin to the osseous Surgical Crown Lengthening treatment of overerupted teeth to correct crest with a . It is also Crown lengthening is a surgical the occlusal plane; presence of subgingival important to remember that the straight procedure performed on a healthy caries; and presence of a subgingival and interproximal surfaces have different periodontium that requires exposure of crown or tooth fracture, root perforation, requirements. In health, the facial aspect adequate tooth structure for restorative or subgingival root resorption (Figure has approximately a 3 mm depth from purposes (Figure 3). Several techniques are 4). Esthetic considerations include the gingival margin to the osseous crest. available, depending upon the proposed changing a “gummy smile,” and marked The interproximal surfaces have a gingival location of the restorative margin, the discrepancies in the height of the gingiva margin to osseous crest depth ranging location of the alveolar crest and gingival around teeth in the esthetic zone. from 3 to 4.5 mm. The interproximal margin, the width of the keratinized Esthetic needs may also demand depth varies depending on the amount of attached tissue, and the amount of orthodontic eruption prior to surgical the scallop of the gingival tissue relative exposed tooth structure available. crown lengthening to maintain existing

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Figure 3g. Palatal view of maxillary left pre-osseous Figure 3h. Buccal view of healing post-crown- Figure 3i. Palatal view of healing post-crown- resection. lengthening surgery showing amount of clinical crown length lengthening surgercy showing amount of clinical crown length gained on buccal. gained on palatal.

Rapid orthodontic forced eruption14 (two to six weeks) can be followed by surgical crown lengthening as long as the tooth is stabilized. It is not always necessary to wait for bone maturation of the attachment that follows with the eruption. Another indication for forced eruption prior to crown lengthening with osseous resection is teeth adjacent to implants Figure 3j. Buccal view of final restoration (final Figure 3k. Palatal view of final restoration. or future implant sites. Random alveolar restoration by Dr. Michelle IKoma). crest reduction of partially edentulous ridges to achieve a flat positive bone architecture adjacent to the treated tooth is contraindicated. gingival contours. This is most common in to surgical crown lengthening is that the anterior maxilla with a high smile line postsurgically, the crown-to-root ratio Contraindications (Figure 5). remains virtually the same or is improved Contraindications for surgical crown The traditional forced-eruption compared to that obtained with surgery lengthening include teeth that are technique causes the gingival tissues to alone. In addition, supporting bone from nonrestorable, teeth or adjacent teeth that erupt with the tooth (Figure 6). A minor the adjacent teeth does not have to be would be compromised either functionally periodontal surgical procedure is then sacrificed to obtain sufficient clinical crown or esthetically, and teeth whose value necessary to return the gingival margin length for the tooth requiring treatment. is not compatible with the procedures to its proper location. There are several The disadvantage of forced eruption necessary to save it. The advantages advantages that forced eruption prior to is that the diameter of the root decreases of retaining a tooth in terms of its surgical crown lengthening provide as as the preparation moves apically. The significance to the overall treatment plan opposed to surgery alone that may be final restoration will therefore exhibit a must be weighed against the extent of significant in varied clinical situations. greater degree of taper from the gingival the procedures needed to properly restore In the maxillary anterior zone, forced margin to the incisal edge. This will the tooth. This is especially important eruption places the gingiva and underlying require greater attention to the gingival today with the accessibility to highly bone around the erupted tooth at a more areas to avoid overcontoured margins. In predictable dental implants. Other factors coronal position. When surgical crown addition, tooth preparation of the smaller to evaluate when considering crown lengthening is completed, the surgeon root segment will require modification lengthening procedures are the crown-to- is able to place the gingival tissues and if one is to achieve a healthy blending root ratio after the tooth is restored and osseous crest at a level that will be more of restorative materials, gingival health, the ability of the patient to maintain the conducive to a cosmetic result. and esthetics. Teeth with moderate to periodontium in a state of health after Another significant advantage to severe tapering of the root form are the restorative procedures have been orthodontically erupting a tooth prior contraindicated for forced eruption. completed.

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Restorative Requirements It is extremely common to find short clinical crowns, which pose a problem to the restorative dentist during crown and bridge procedures. Schwartz and Figure 4a. Buccal view of mandibular left shwoing Figure 4b. Lingual view of mandibular left showing 23 colleagues found that loss of retention short clinical crowns. short clinical crowns. was the second most frequently encountered complication following caries development in fixed partial dentures. When undiagnosed for some time, loss of retention can lead to serious problems. In an attempt to reduce the risk of loss of retention, the abutments should be prepared following a carefully chosen design and not prepared further subgingival. A review of the ideal tooth preparation requirements follows:24 Figure 4c. Buccal view of mandibular left showing gain nnAdequate length for proper retention in clinical crown length after osseous resective surgery. Figure 4d. Surgical crown lengthening to gain clinical and resistance. The ideal preparation crown length allows the restorative dentist to gain retention without placing restorative margins subgingival. Note the must have at least 4 mm of axial wall tissue health obtained when restorative margins are placed at height with a minimum of 2 to 3 mm of thte ginfival margin (final restoration by Dr. Blake Mueller). sound tooth structure circumferentially and a maximum convergence angle of 6 to 10 degrees. nnSufficient axial reduction for adequate esthetic rendition. Metal-ceramic and coronally positioned in the interproximal of the biologic width in the interproximal all-ceramic crowns require 1.5 to 2 mm zones. During crown preparation, it area, which is the most susceptible area. of tooth reduction to allow proper is easy to continue the interproximal thickness of the ceramic veneer. crown margin at the same level as the Treatment Plan and Sequence nnSufficient occlusal reduction for buccal or lingual margin and violate the Prior to crown lengthening occlusal function and anterior biologic width interproximally. This is procedures, a combined periodontal and guidance. Metal ceramic crowns require most common when preparing anterior restorative treatment plan is essential. The 2 mm of occlusal reduction, less if full teeth, as crown margins are placed sequence of therapy is very important to cast gold restorations are utilized. subgingivally for cosmetic purposes, and achieve desired clinical results. Diagnostic In the anterior maxilla, Kois25 has the underlying osseous scallop changes procedures include periodontal probing advocated having at least 2 mm of solid so dramatically from the straight to the depths and radiographs to determine root tooth structure on the buccal and lingual interproximal surfaces. form, root proximity, and bone levels. An surfaces of the tooth preparation. Kois Kois recommends avoiding the use of esthetic examination includes evaluation recommends finishing the interproximal flat-end diamond burs when extending of the smile line (position of the upper margin parallel to the cementoenamel beyond the line angles. The tendency is lip relative to incisal edge position and junction without being concerned with to follow the flat shoulder margin from gingival facial levels, i.e., the amount the 2 mm rule of solid tooth structure, the straight buccal surface past the line of gingival exposure during speech as as long as the margin is on sound tooth angle into the interproximal. Adjustment well as smiling).13 The tissue type and structure. The scalloped tissue form in the depth of the interproximal margin the amount of keratinized tissue along follows the cementoenamel junction and using a round-end tapered diamond bur is with the patient’s esthetic concerns, underlying osseous crest, which is more recommended. This will prevent violation desires, and expectations are extremely

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Creating a level osseous contour that allows the soft tissue to follow is an important concept for long-term periodontal stability and maintenance.

Figure 5a. Patient presents with short clinical anterior Figure 5b. Close-up view of patient’s short clinical If the margin is close to the osseous teeth, resulting in a “gummy smile.” anterior teeth (not flat architecture of periodontium). crest (as is often the case with fractured teeth or extensive decay) resulting in excessive ostectomy that will compromise the adjacent teeth, orthodontic forced eruption of single rooted teeth can be considered.27 Decay extending close to furcations on molars can be evaluated for possible root amputation procedures. The restorative requirements postsurgery in the remaining furcations is the same as described. i.e., 3 mm margin to osseous crest. If this cannot be achieved, the Figure 5c. Surgical crown lengthening was completed Figure 5d. Postsurgical results showing significantly nonrestorable tooth should be extracted. to lengthen anterior clinical crown length. improved anterior cosmetics. Combined implant and conventional restorative treatment in the anterior zone should always be carefully analyzed. If crown lengthening is required on the teeth adjacent to implant sites, this procedure should precede the implant placement. Once healing has occurred important. The prognosis of the tooth or restorations fabricated. This will help with a stable desired gingival architecture, teeth to be treated along with the adjacent reduce the inflammatory component of the implants can be placed with the teeth is required. Compromising the the dentogingival complex and permit hex platform at the desired vertical adjacent dentition to save a tooth with re-evaluation of tissue response before height relative to the teeth. It is very a poor prognosis is a contraindication deciding what type of surgical correction easy to misjudge this if the amount of to treatment. Alternative options such is necessary. If endodontic treatment osseous reduction has not already been as implants or fixed partial dentures is indicated, root canal therapy should determined and completed. Once the should be considered. Mounted casts be completed prior to the surgery. This implant is placed, it is impossible to with a diagnostic wax-up of the future will prevent later surprises, especially correct. If bone level changes are not restorative plan are always indicated. if extensive decay exists under old anticipated, then implant placement can Once the ideal future crown contours restorations. It is always better and easier precede soft tissue alterations. This can have been established, the restorative and to make a judgment regarding prognosis usually be performed simultaneously with periodontal team can work in reverse to when the restoration and decay have been the second stage implant procedure. achieve the desired clinical results. removed. Removal of the provisional Initial therapy includes scaling and restorations at the time of surgery Healing root planing and providing the patient facilitates access to the interproximal In non-esthetic (posterior) areas, the with oral hygiene instructions. A areas and allows the periodontist to make patient should be re-evaluated six weeks provisional restoration should be placed the important decision about how much postsurgery prior to continuing with prior to the surgical procedure. When ostectomy (removal of supporting bone) final restorative procedures. Margins inadequate restorations exists, they is enough. It is important to remember should be kept at the gingival margin. should be removed and proper provisional that this is not a one-tooth procedure. In the anterior esthetic zone, a longer

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healing period is recommended. Wise recommends waiting 21 weeks for soft tissue gingival margin stability.28 Kois has suggested waiting longer.25 During final tooth preparation, Figure 6a. Chronic gingival inflammation around crown Figure 6b. REmoval of the restoration No. 8 shows margins should be placed supragingival restoration No. 8. restorative margin placed deep into gingival sulcus. or, if cosmetic concerns direct, at the gingival margin. If cosmetics dictate subgingival margin placement, the dentist preparing the teeth should not only be aware of the cementoenamel junction and soft tissue form, but should also again sound to bone. Studies in the periodontal literature indicate that the postsurgical dimension of biologic width will approximate the amount present prior to surgery.29,30

It is as important postsurgically as it is Figure 6c. Orthodontic extrusion was completed to Figure 6d. Final restoration No. 8 just slightly below prior to surgery to keep in mind that the coronally position osseous and gigival tissues prior to crown gingival margin shows improved gingival health (final location of a restorative margin relative lengthening surgery. restoration by Dr. Gary Solnit). to the crest of the alveolar bone is more critical for preserving gingival health that its distance below the free gingival margin. (Kois recommends keeping the of the soft tissues. Loe10 showed that hide a margin subgingivally in a thick margin 3 mm from the osseous crest.5) with normal pressure, part of the periodontium as compared to thin Prior to final margin placement, the retraction cord could impinge into the tissue. Depending on the thickness of restorative dentist should identify the biological width. Excessive tearing of the the tissue, a certain amount of rebound level of the soft tissue in relation to dentogingival complex and inappropriate of the soft tissue is expected. It can take the osseous crest before the retraction use of chemicals (buffered 14 percent one to three years for the final mature cord is placed. If this relationship is not aluminum chloride, Hemodent solution) tissue architecture to reform. It is not properly identified, as the biologic width used to control gingival crevicular fluid practical to keep patients in provisional redevelops, the preparation margin can and bleeding will induce recession, restorations for so long. The important easily end up being too far subgingival. exposing crown margins. It is safe to aspect of this concept is to place a final As described earlier, this relationship can leave the impregnated cord up to 15 restoration that does not impinge the set the stage for progressive periodontal minutes. Depending on the thickness of gingival embrasure and allows space breakdown. the gingival tissue and the sulcus depth for the interproximal gingival tissue Use of a rotating instrument beneath encountered, Chiche32 recommends a to rebound. The final restoration the gingival margin traumatizes the single string or selective double-string should be fabricated to allow for final gingival, sulcular epithelium, and possibly technique. It is important to distinguish maturation of the gingiva and rebound even the gingival attachment. The trauma between thick and thin gingival tissue of the interproximal gingival tissue. caused by a rotating instrument may because the tissue behaves differently As long as the apical end of the final be reversible.31 However, in some cases, when it is surgically manipulated. It crown restoration is 5 mm or less from permanent loss of periodontal attachment is easier to maintain papilla height the interproximal bone, Tarnow ; found may result.10 postsurgically with thick tissue. Thin that a papilla was always maintained or Tissue retraction is a traumatic tissue tends to shrink more. In respect reformed postsurgically. procedure requiring gentle manipulation to crown margin placement, it is easy to

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64:240-1, 1993. Conclusion 20. Wagenberg BD, Eskow RN, and Langer, Exposing adequate In the past, esthetics usually tooth structure for restorative dentistry. Int J Periodont Restor Dent 9:323-31, 1989. demanded subgingival margin 21. Nevins M and Skurow HM, The intracrevicular restorative placement. Current porcelain materials margin, the biologic width, and the maintenance of the gingival should allow more restorative margins margin. Int J Periodont Restor Dent 4:30-9, 1984. 22. Ochsenbein C and Ross S, A re-evaluation of osseous to be finished at the level of the soft surgery. In, Prichard J, ed, Dental Clinics of North America. WB tissue. If the ideal relationship between Saunders Co, Philadelphia, pp 87-102, 1969. bone and margin is respected, a healthy 23. Schwartz N, Whitsett L, et al, Unserviceable crown and fixed partial dentures: life span and causes for loss of periodontium will follow. serviceablility. J Am Dent Assoc 5:60-8, 1979. 24. Shillingburg HT, Jacobi R, and Brackett SE, eds, References Fundamentals of Tooth Preparations. Quintessence, Chicago, 1. Garguilo AW, Wentz FM, and Orban B, Dimensions and 1987, pp 1-43. relations of the dentogingival junction in humans. J Periodontol 25. Kois J, The periodontal-restorative interface (lecture), AAP 32:262-7, 1961. meeting, Boston, Mass, 1998. 2. Cohen DW, Biologic width (lecture). Washington DC, Walter 26. Ingber JS, Forced eruption, II: A method of treating non- Reed Army Medical Center, June 3, 1962. restorable teeth -- periodontal and restorative considerations. 3. Maynard JG Jr. and Wilson RD, Physiologic dimensions of J Periodontol 47:203-16, 1976. the periodontium significant to the restorative dentist. J 27. Wise MD, Stability of gingival crest after surgery and Periodontol 50:170, 1979 before anterior crown placement. J Prosthet Dent 14:20-3, 4. Ingber FJS, Rose LF, and Coslet JG, The biologic width: A 1985. concept in periodontics and restorative dentistry. Alpha 28. Van der Velden U, Regeneration of the interdental soft Omegan 10:62-5, 1977. tissues following denudation procedures. J Clin Periodont 5. Kois J, Altering gingival levels: the restorative connection, 9:455-9, 1982. Part 1: Biologic variables. J Esthet Dent 6:309, 1994. 29. Smith DH, Ammons WF Jr, and Van Belle G, A longitudinal 6. Reichen-Graden S and Lang NP, Periodontal and pulpal study of periodontal status comparing osseous recontouring conditions of abutment teeth. Status after four to eight years with flap curettage, I: Results after six months. J Periodontol following incorporation of fixed reconstructions. Schweiz 51:367-75, 1980. Monatsschr Zahnmed 99:1381-5, 1989. 30. Ramfjord SP and Costich ER, Healing after simple 7. Valderhaug J, Periodontal conditions and carious lesions gingivectomy. J Periodontol 34:401-15, 1963. following the insertion of fixed prostheses: a 10-year follow-up 31. Chiche G, Esthetics of Anterior Fixed Prosthodontics. study. Nit Dent J 30:296-304, 1980. Quintessence, 1994, Chap 4. 8. Valderhaug J, A 15-year clinical evaluation of fixed 32. Tarnow DP, Magner AW, and Fletcher P, The effect of the prosthodontics. Acta Odontol Scand 49:35-40, 1991. distance from the contact point to the crest of bone on the 9. Silness J, Periodontal conditions in patients treated with presence or absence of the interproximal dental papilla. J dental bridges, J Periodont Res 5:225-9, 1970. Periodontol 63:995-6, 1992. 10. Loe H, Reaction of marginal periodontal tissues to To request a printed copy of this article, please contact: David restorative procedures. Int Dent J 759-78, 1968. F. Levine, DDS, 3808 W. Riverside Drive, #3051, Burbank, CA 11. Dragoo M, Periodontal tissue reactions to restorative 91505-4325. procedures. Int J Periodont Restorative Dent 1:9-23, 1981. 12. Parma-Benfenati S, Fugazzoto PA, and Ruben MP, The effect of restorative margins on the postsurgical development and nature of the periodontium, Part I. Int J Periodont Restorative Dent 6:31-51, 1985. 13. Allen EP, Mucogingival surgical procedures to enhance esthetics. Dent Clin North Am 32:307-31, 1988. 14. Rosenberg ES, Garber DA, and Evian CI, Tooth lengthening procedures. Compend Contin Educ Dent 1:161-73, 1980. 15. Holmes JR, Sulik WD, Holland GA, and Bayne SC. Marginal fit of castable ceramic crown. J Prosthet Dent 67:594-9, 1992. 16. Christensen GJ, Marginal fit of gold castings. J Prosthet Dent 16:297-305, 1966. 17. Waerhaug J, Subgingival plaque and loss of attachment in as observed in autopsy material. J Periodontol 47:636-42, 1976. 18. Waerhaug J, The angular bone defect and its relationship to trauma from occlusion and downgrowth of subgingival plaque. J Clin Periodontol 6:61-82, 1979. 19. Mishkin D, Gellin R, Letter to the editor. J Periodontol

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The Emperor’s New Dental Smock

t should be obvious to anyone who has triumvirate of Marcus Welby, Ben Casey not spent his waking hours during the and Dr. Kildare dictated health care past year cataloguing the indiscretions costuming for years despite the fact that of our national leader that notable not one of them knew a speculum from changes are taking place within a matrix band. It was during the latter Iour profession. part of this era that skirts for auxiliary Specifically, I speak of the costuming personnel disappeared almost overnight, we embrace as health professionals. It much in the same way an impacting as- is important that the public can readily tral body is supposed to have wiped out differentiate us from other professional the dinosaur population. Robert E. persons such as those engaged in public Enter the Sixties. This was a period Horseman, DDS landfill projects or employed in the service when “doing your own thing” became of the Good Humor Company. paramount and, to people of my genera- In the early days of dentistry, when tion, indicated that the Decline of Civiliza- long frock coats and vests festooned with tion initiated by the Beatles had gone into gold watch chains and elks’ teeth were warp speed. To dentists young enough considered de rigueur for dentists, black not to recognize the names of Fred Allen, was the color that most nearly expressed the Ritz Brothers, Horace Heidt and Glen the seriousness-of-purpose (SOP) we Gray, the opportunity to state their new wished to project. It could also be worn SOP was not to be missed. White was daily for upward of a month without vis- definitely passé. Pastels were hot, as were ible blood splatters -- certainly a plus in paisleys and tie-dyes. T-shirts with clever those pre-high-volume-evacuation days. messages such as “I’m with Stupid” were Additionally, the attire was appropriate at common enough that we could all express a formal wedding, a funeral or the ribbon- our individuality in unison. The freedom cutting ceremony at a new livery stable. from frequent barbering as well as an Its equal as an all-purpose uniform has unlimited selection of footwear were the never been matched. most precious things to have evolved since Suddenly, however, black was out and the advent of Bis-gma. Dentists, in many white was in. White represented purity, instances, were difficult to distinguish from sterility and a new SOP as opposed to, members of the Cirque du Soleil. Not only say, candy apple red or hot pink. Backed did they suffer no embarrassment from by a coalition of button manufactur- this, they openly advertised it in the media, ers and laundry operators, the medical offering the opinion that cowards had little

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The Emperor’s New Dental Smock

to fear from them, providing they pre- a compassionate heart lurks, the effect is sented with a valid insurance plan. Little enough to allay the qualms of the most did we suspect that just around the corner fearful. Below the logo is the wearer’s a brand-new seriousness-of-purpose was name (first only -- we’re friendly folks) about to be unleashed. and rank. The dentist has his or her title OSHA took a good look at our uni- of “DENTIST” boldly depicted so there’s forms and opined that we were the laugh- no question about who’s the boss. ingstock of the infectious germ world. It is not unusual to see a dentist and Let us cover every bodily surface, it said, staff all sporting the team outfit milling with something as impervious to bacteria about in lockstep at one of the Scientific as Kevlar is to bullets. Spray it with Lysol Sessions. It brings to mind ducklings and discard it at the end of each patient that have passionately imprinted on their encounter, the recommendation went. mother. Unfortunately, once the OSHA God forbid you should launder it at home, stuff has been donned, all this is lost to it warned. the patient, but the staff is aware of who At the same time OSHA was directing and what they are and that’s enough to infection control, large corporate struc- sustain them between paydays. tures were sticking their noses into the We may be in the last throes of indi- tent with managed care ideas. Individu- vidualism on this planet. My observation alism was in the decline, but uniform of past and current sci-fi movies confirms purveyors were not caught napping at that before long, all of us will be wearing a their Singers. The emphasis now shifts to uniform of silver lamé spandex. All of us the Dental Team. -- and that includes visiting aliens with the To impress patients with the concept exception of those with multiple tentacles of intensive team efficiency, modern -- will be encased in seamless, shiny, form- dental office personnel can appear united fitting suits. Authority will be vested in in SOP by wearing identical uniforms. It the timbre of one’s voice, which should works for McDonalds and K-Mart, the be similar to that projected by James Earl reasoning goes. Jones. It couldn’t hurt to have one of those Personalized with an office logo, a typ- Star Wars wands that go woom, woom! ical dental outfit features a little smiling when waved at an antagonist. molar brandishing a in one Dentists would be well-advised to “hand” and a floss container in the other. keep this in mind when ordering supplies. Embroidered over an area beneath which

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