Principles in metallic RPD design
11-5-2016By : Cezar LahhamSupervisors : Dr Walla’ Hamadneh Dr Mutaz Arman
Outline :
Chapter 4: Biomechanics of RemovablePartial Dentures
Chapter 10: Principles of
Removable Partial Denture Design
1- Revision : 4 min
2-
Kennedy Classification
Support Types
Totally Tissue support Tooth-tissue support Totally tooth support
Canadian dentist, in 1926 Ante's law refers to a group of proposals related to crown-to-root ratio
Support
Class I + II = Tooth-tissue Support Class III + IV = Totally tooth support or
tooth-tissue support
Ref; http://www.oxfordreference.com/view/10.1093/oi/authority.20110803095415976
RPD Components
Fulcrum Line
Lever
In RPD !!!
Rest
Connector
Lever Class 1
Video::: class 2
prosto_0001.wmvprosto 2_0001.wmv
12
Clasp
Class III :
The Design of RPD
Who draw the design of RPD ??
The Design of RPD
- Simple- Obtain good base adaptation- Use what is present (e.g. existing rest seats)- Plan for the future- Occlusion- At the end of treatment
Steps
1- determine the Class 2- Type of support 3- OSCAR
outlineSupport
Connectors
Retention
:rests + indirect retainers
Components design
Rest : Incisal,Lingual,Embrasure,occlusal,Onlay
IR: Double bar,Strap ,occlsal,…. Connectors : -Upper: 1-Full Palatal plate 2-AP.P.P 3-A P P 4-P strap -Lower :1-Lingual bar 2-Double lingual 3-L. Strap
4-Labial bar
Revision
Clasps : Supra&infralbulge1-Circlet 2–embrasure”double aker’s”3-Ring 4-reverse action “fish hock”5-Onlay6-back action7-continous
Revision
RPI system
RPA system
Combination clasp
Half and half clasp
Revision
Class I + IITooth-tissue support
Rest:Mesially
Indirect Retainer
Connectors
Clasps infra
Class III + VI
Tooth support
Rests: close to the edentulous area
No need to indirect retainer
Connectors
Clasps supra
Examples ::
References