Chapter 1 Introduction

Home , Dentures, Fixed prosthodontics, Prosthodontics

CHAPTER 1 FIXED PROSTHODONTICS is the branch of prosthodontics concerned with the replacement and/or restoration of teeth by INTRODUCTION artificial substitutes that are not removable from the mouth.1

REMOVABLE PROSTHODONTICS DEFINITIONS is the branch of prosthodontics concerned with the replacement of teeth and contiguous PROSTHETICS is the art and science structures for edentulous or partially of supplying artificial replacements for edentulous patients by artificial substitutes missing parts of the human body and a that are removable from the mouth.1 PROSTHESIS is an artificial replacement for an absent part of the human body. MAXILLOFACIAL PROSTHETICS is the branch of prosthodontics concerned with By supply the suffix -DONTICS, the restoration and/or replacement of which connotes dentistry, the term somatognathic and associated facial structures prosthodontics is derived. by artificial substitutes that may be removed PROSTHODONTICS or PROSTHETIC on a regular or elective basis.1 DENTISTRY is defined as the branch of dentistry pertaining to the restoration and PROSTHODONTIC RESTORATIONS maintenance of oral function, comfort, appearance, and health of the patient by the RESTORATION is a broad term restoration of natural teeth and/or the applied to any material or prosthesis that replacement of missing teeth and contiguous restores or replaces lost tooth structure, teeth, oral and maxillofacial tissues with artificial or oral tissue.1 substitutes.1 More simply stated, prosthodontics is the restoration of natural Single tooth restorations include teeth and the replacement of missing teeth and amalgams, composite resins, inlays, onlays, associated structures with artificial substitutes. crowns, and veneers. The restoration of natural teeth with single tooth restorations is THE DIVISION OF PROSTHODONTICS frequently referred to as RESTORATIVE or OPERATIVE DENTISTRY although this Prosthodontics has three major treatment is included in the definition of divisions: (1) fixed prosthodontics, prosthodontics. (2) removable prosthodontics, and (3) maxillofacial prosthetics. Removable A DENTURE is an artificial substitute prosthodontics is subdivided into removable for missing natural teeth and adjacent tissues.1 partial denture prosthodontics and complete A PARTIAL DENTURE (PD) is a dental denture prosthodontics. prosthesis that restores one or more, but not all PROSTHODONTICS of the natural teeth and/or associated parts (of a dental arch) and is supported by the teeth and/or mucosa; it maybe fixed or removable.1 FIXED REMOVABLE MAXILLOFACIAL A FIXED PARTIAL DENTURE (FPD) is a PD that is luted to natural teeth or tooth roots and/or affixed to dental implants that furnish PARTIAL DENTURE COMPLETE DENTURE the primary support for the prosthesis.1 The

1-1 term BRIDGE is a non- professional term for bar clasp or "infra bulge" clasp was by FPD which, although common in lay person's Henrichsen10 in 1914, but the bar clasp did not vocabulary, should be avoided. A FPD can gain popularity until Roach promoted this not be removed from the mouth by the patient. concept in 1930.11 These early references in A REMOVABLE PARTIAL DENTURE the literature concerning RPD prosthodontics (RPD) is a PD that can be removed from the recorded the technics of the authors and mouth and replaced at will by the patient.1 A illustrate the ART of prosthodontics. UNTIL COMPLETE DENTURE (CD) is a dental THE 1950'S, RPD CONCEPTS WERE prosthesis that replaces the entire dentition MOSTLY DEVELOPED BY A SMALL and associated structures of the maxillae or GROUP OF AUTHORS WHO PRESENTED mandible.1 The term APPLIANCE should not THEIR THEORIES, EMPIRICAL be used when referring to a denture. An oral OBSERVATIONS, PHILOSOPHICAL appliance is a device worn by a patient to BIASES AND CLINICAL/LABORATORY effect some sort of treatment such as moving TECHNICS. teeth or radiating tissues. The terms restoration, prosthesis, and denture are As a SCIENCE, RPD prosthodontics synonyms. essentially began in the 1950's with cross- sectional population studies performed in THE DEVELOPMENT OF RPD England, Scandinavia and Switzerland that PROSTHODONTICS showed extensive pathologic changes in the periodontium and increased caries activity for There is historical evidence that man patients who wore RPDS.12-17 In 1956 the has been replacing missing teeth since at least first attempts to evaluate RPD design theories 2500 B.C. The first mention of a RPD in the through in vitro studies using partially literature was by Heister in 1711. He edentulous arch/RPD analogs were described making a RPD by carving a block of reported.18,19 Since about 1965 the science of bone to fit the mouth.2 In 1728 Fauchard RPD prosthodontic has expanded described making a mandibular RPD by exponentially with in vivo and in vitro joining two carved blocks of ivory together by research reports.20-45 CLINICAL metal labial and lingual connectors.3 Balkwell RESEARCH HAS CONFIRMED THAT RPD wrote of a maxillary RPD with a palatal TREATMENT IS VIABLE AND DOES connector in 1880.4 Retentive clasps were NOT, IN ITSELF, CAUSE PERIODONTAL first discussed by Mouton in 1746.5 Delabarre DESTRUCTION, CARIES OR TOOTH referred to "hooks" (clasps) and the use of MOBILITY.38-45 It is important to note that "little spurs" (occlusal rests) to prevent research results are less conclusive about the irritation around the abutment teeth.6 In 1810, specifics of RPD design. Gardette described the use of the wrought band clasp.7 In 1899, Bonwill recorded his Recognizing the tremendous growth of technics for clasping abutments with knowledge which was occurring in dentistry, individually contoured gold circumferential the American Dental Association established clasps that were then soldered to "the plate" prosthodontics as a dental specially in 1950. (major connector).8 Bonwill also advocated In this way prosthodontics is divided into a the use of "lugs" (rest seats) so the prosthesis DISCIPLINE studied and practiced by general would be supported by the abutments . In dentists and a SPECIALTY studied and 1913, Roach presented a wrought wire practiced by Prosthodontists. circumferential clasp as an improvement over A PROSTHODONTIST is a dental the wide band clasp.9 The first mention of a specialist engaged in the practice of

1-2 prosthodontics. To become a prosthodontist a eligible to apply for examination by the dentist must successfully complete an American Board of Prosthodontics. This accredited advanced education program in individual is termed an EDUCATIONALLY prosthodontics. In the United States, the QUALIFIED PROSTHODONTIST.1 A Commission on Dental Accreditation of the prosthodontist who's application for the American Dental Association (ADA) accredits examination has been accepted and is current, advanced education programs. is termed a BOARD ELIGIBLE PROSTHODONTIST. One who has passed Prosthodontic programs are thirty- the examination is considered a BOARD three months in length and lead to a CERTIFIED PROSTHODONTIST.1 CERTIFICATE in Prosthodontics, or a MASTER'S DEGREE in DENTISTRY or a A DENTURIST is a nondentist of MASTER'S DEGREE in a basic science and a limited dental knowledge and skills licensed CERTIFICATE in Prosthodontics. to provide dentures for a patient.1 DENTURISM is the often illegal procedure Accredited prosthodontic training wherein a nondentist engages in the practice programs are located in dental schools, of making impressions and fabricating hospital dental programs and dental clinics dentures for a patient.1 Denturism is legal in throughout the United States. Separate Arizona, Colorado, Idaho, Maine, Montana, programs in maxillofacial prosthetics are Oregon and Washington. available. They are usually of one year duration and require completion of a THE SCOPE OF RPD prosthodontic program for admission. PROSTHODONTICS

Prosthodontic training programs are Removable partial denture very rigorous and time consuming. Dentists prosthodontics is a vast subject dealing with completing these programs will have the following: advanced knowledge and experience in the 1. The evaluation of the patient basic sciences; dental materials; prosthodontic for treatment. diagnosis and treatment planning; treatment 2. Providing the dental treatment planning preprosthetic oral surgery and necessary to prepare the mouth implant placement; occlusion; esthetics; for the RPD. treatment of patients with TMD and facial 3. Constructing and fitting the pain; restoration of tooth structure; RPD. replacement of missing teeth with FPDs, 4. Educating the patient in the RPDs, CDs and implant prostheses; the use of use, maintenance and what to dental articulators; precision and expect from RPDs. semiprecision attachments; and the restoration 5. Maintaining the natural teeth of missing oral and facial structures with and soft tissues. prosthesis and geriatric prosthodontics. RPD prosthodontics encompasses all Prosthodontists are indeed specialists in disciplines of dentistry. The dentist providing reconstructing teeth, mouths and faces with RPD treatment must be knowledgeable in all prostheses. aspects of dentistry and technically capable of providing the treatment he/she will render. In the Untied States, a prosthodontist who has successfully completed an advanced education program, accredited by the ADA, is

1-3 INDICATIONS FOR RPDs THE OBJECTIVES OF RPD TREATMENT A RPD should be a treatment consideration whenever the dental arch can The objective of RPD treatment is to not be restored with a FPD, implant FPD or restore the patient's mouth to an acceptable implant-tooth FPD. The primary indications level of oral health in such a way that the RPD for RPDs are: does not cause damage to the oral structures. The restoration should restore acceptable 1. FPD Not Possible esthetics and masticatory efficiency as well as If a FPD is not possible provide patient comfort and well-being. To because of the length of the achieve this objective dental treatment must edentulous space, lack of be provided to professional standards by a alignment of the abutments for knowledgeable and capable dentist. a path of placement of the FPD, or inadequate length of the THE NEED AND DEMAND FOR RPD clinical crowns of the abutment TREATMENT teeth for retention and resistance form, a RPD may be Data from Phase I of the Third the treatment of choice.No National Health and Nutrition Examination Survey (NHANES III) show that in 1988- 2. Distal Abutment Tooth 1991 30.5% of the population in the United Absence of a distal abutment States retained all 28 teeth and 10.5% was tooth precludes restoration with completely edentulous.46 This means that a FPD unless an implant FPD 59% of the population was partially or implant-tooth FPD is edentulous. Tooth loss increased with age. possible. Mexican-Americans had the lowest rates of tooth loss.46 3. RPD Denture Base Is Necessary According to another study, one in five When there is loss of persons 18-74 years of age wears a removable considerable volume of the prosthesis of some type.47 Women wear alveolus (mucosa and bone) a removable prostheses more often than men denture base is necessary for and blacks more frequently than whites.47 esthetics and self cleansing Mexican-Americans are less likely to use prosthesis design. dentures than either of their non-Hispanic counter parts.47 Approximately 60% of 4. Patient Can Not Afford More denture users have at least one problem with a Desirable Treatment denture.47 THUS, DESPITE INCREASING A frequent reason for TRENDS IN TOOTH RETENTION, constructing tooth-supported DEPENDENCY ON REMOVABLE RPDs is that the patient can not PROSTHODONTIC PROSTHESES IS afford the more desirable FPD STILL A REALITY OF LIFE FOR or implant supported FPD MILLIONS OF AMERICANS.47 treatment. The loss of natural teeth is directly related to age. Since the percent of elderly persons in society is increasing and the

1-4 number of completely edentulous persons has 5. Mouton: Essay stabilized, the number of partially edentulous d'odontotechnique, ou patients will likely increase.47-55 dissertaion Sur dents artificielles. Paris, France, The demand for dental care from this 1746,89. healthier elderly population will increase. Since these elderly patients will most likely be 6. Delabarre CF: Discours on limited income and since partially d'ouveture d'un cours de edentulous patients are most likely from fixed medicine dentaire. Paris, income and lower socioeconomic groups, the France, 1817,390. demand for RPD treatment will increase because of the prohibitive cost of FPD and 7. Gardette J: New series. Am J implant treatment. A significant portion of Dent Sc. 1850-1851;379. these patients will be complicated to treat. 8. Bonwill WGA.: New methods Replacing missing teeth by surgically of clasping artificial dentures to placing dental implants and restoring the human teeth without injury edentulous space with a fixed-type implant versus immovable bridges. prosthesis, thus eliminating the need for an Dent Items Interest, 1899;656- RPD, is not always possible because of 670. inadequate bone volume and the surgical risk involved in placing the implants. Frequently, 9. Roach FE: Double bow clasp. treatment with implants is not possible Dent Rev. 1913;27:1007. because of the expense. Thus, despite declining edentulism the 10. Henrichsen SA: Ball clasps for need and demand for RPD treatment will partial dentures. Zahnaeratl remain high in the immediate future and the Orthopaed U Prosthese. 1914 practitioner must be knowledgeable and (review in Dent cosmos) competent to provide that treatment which 1914;56:1194-95. will likely increase in complexity of services required. 11. Roach FE: Principles and essentials of bar clasps partial REFERENCES dentures. J Am Dent Assoc. 1. The glossary of prosthodontic 1930;17:124-138. terms. 6th ed., St. Louis, C V Mosby, 1994. 12. Koivumaa KK: Changes in periodontal tissues and 2. Aldorf: DE Dentium Dolore. supporting structures connected Paris, France, 1718,618. with partial dentures. Proc Finn Dent Soc. 1956;52 (suppl 3. Fauchard P: Le Chirurgien I). Dentiste. Paris, France, 1728. 13. Koivumma KK, Hegegard B, 4. Balkwell FH: Mechanical Carlson GE: Studies in partial Dentistry in Gold and denture prosthesis: II. An Vulcanite. London, UK, investigation of Churchill, 1880. dentogingivally supported

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