Removable partial denture

Summarizes parts of RPD, their functions and principles of how to design an rpd.

Dr. Almas Muhammad Arshad

1. REMOVABLE PARTIAL DENTURE – Parts, Functions, Principles of design Dr. Almas Muhammad Arshad House Officer Prosthodontic Department UCD, UOL

2. OBJECTIVES OF PROSTHODONTIC REPLACEMENT Restoration of esthetics Restoration of function Preservation of health

3. REMOVABLE PARTIAL DENTURE: “A removable prosthesis that replaces missing teeth in a partially dentate arch, and can be removed or replaced by the patient himself.”

4. TYPES Acrylic partial denture Temporary dentures Cast partial denture

5. Interim denture Enhance the esthetics, stabilization and/or function for a limited time Later replaced by definitive prosthesis Transitional denture An interim denture in which artificial teeth are added as natural teeth lost Treatment denture Used for the purpose of treatment or conditioning of tissue Post surgery TEMPORARY REMOVABLE PARTIAL DENTURES

6. PARTS OF RPD:

7. MAJOR CONNECTORS Unification Distribution of applied forces Provides cross-arch stability to help resist the displacement by functional stresses.

8. MANDIBULAR MAJOR CONNECTORS : Lingual Bar (All situations where min 8mm space coverage is req ) Sub-lingual bar (Distance of floor or mouth to gingival margin is < 6mm)

9. Continuous Bar (Wide diastema ) Labial Bar (Severe lingual inclinations)

10. MAXILLARY MAJOR CONNECTORS: Single palatal strap (Bilateral short span edentulous spaces) Single palatal bar (Interim partial dentures) Anterior posterior palatal strap (All Kennedy situations, Multiple saddle areas)

11. Anterior posterior palatal bars (Kennedy Class II and IV ) Complete Palatal plate (Distal extension conditions, Cleft palate, Heavy occlusal forces) U shaped (Inoperable tori, Least suitable design)

12. MINOR CONNECTORS Functions Transfers functional stresses to abutment teeth Maintain a path of insertion Base Other Components (Clasps, rests, Indirect retainers)

13. RESTS AND REST SEAT Provides vertical support Transfers the forces along the long axis of teeth Positional maintenance Rest Seat: The prepared surface on the abutment teeth to receive the rest

14. Types: Occlusal Incisal Cingulum

15. DIRECT RETAINERS Component of RPD that functions to retain and prevent the dislodgement of the denture

16. TYPES OF CLASP: Cast circumferential clasp Bar Clasp

17. PRE FABRICATED ATTACHMENTS

18. INDIRECT RETAINERS Stabilization Prevents the rotational displacement of rpd Functions through lever action on opposite side of the fulcrum line

19. FULCRUM LINE An imaginary line around which the denture tends to rotate.

20. DENTURE BASE Support, retention, stress distribution, esthetics Maxillary denture base  Maxillary Tuberosity area Mandibular denture base  Retromolar pad

21. ARTIFICIAL TEETH Types of artificial t eeth: Acrylic Porcelain Metal Tube teeth

22. PRINCIPLES OF RPD DESIGN

23. Design of removable partial denture should be Simple Comfortable Harmless to the remaining teeth PRINCIPLES OF RPD DESIGN

24. BIOLOGICAL CONSIDERATION Teeth and periodontal tissue Inclination of abutment Status of residual ridge Types of edentulous ridge Occlusion

25. Good Support but poor stability Poor Support Poor Stability Poor support and poor to fair stability

26. MECHANICAL CONSIDERATION Retention Stability Support

27. How the RPD is supported? Tooth Supported Kennedy class 3 and 4 Tooth – Tissue Supported Kennedy Class 1 and 2 Away from abutment  Tissue Support Adjacent to edentulous area  Tooth support Quality of Ridge and accuracy of impression is the key

28. Connecting the tooth and tissue support units Major Connector – Rigid for proper distribution of load Minor connector SUPPORT

29. How the RPD is to be retained Natural Sources Frictional resistance Interfacial surface tension Palatal vault Occlusion Clasp assembly (avoiding torqueing forces) Splinting RETENTION

30. Connecting the Retention units to the supporting units Indirect Retainers - STABILIZATION Outlining and joining the edentulous area to already established design

31. SEQUENCE OF DESIGN RPD

32. References McCraken’s Removable partial prosthodontics A.B Carr David T Brown 12 th edition

33. THANK YOU