Section C: Removable Prosthodontics - Complete and Partial Dentures
What Section C covers
Section C tests the biomechanics and clinical sequencing of removable prostheses. For complete dentures, know the neutral zone, border molding, posterior palatal seal, centric relation record, and the difference between maximum intercuspation and a centric relation record. Understand denture base extension, support (bone and mucosa), and the role of a remount and occlusal adjustment after processing to correct processing errors.
Partial dentures
For removable partial dentures, know Kennedy classification and Applegate's rules, and understand that classification should follow the most posterior edentulous area. Know component function: rests transmit force along the long axis, direct retainers (clasps) provide retention, indirect retainers resist rotation, major connectors distribute load, and guide planes aid stability and path of insertion. Understand stress distribution and why rigid major connectors and properly placed rests matter.
Traps
- Classifying by the anterior space rather than the most posterior edentulous area.
- Confusing retention (resisting displacement) with stability (resisting horizontal forces) and support (resisting vertical forces).
- Assuming more clasp coverage is always better; it can increase load on abutments.
- Skipping the post-insertion remount and occlusal adjustment.
Rule of thumb
For any partial denture question, ask: where is the fulcrum, and what resists rotation about it? That usually points to the indirect retainer and the need for rigid major connectors.
Worked example: A Kennedy Class II modification with a distal extension: the indirect retainer should be placed as far anterior as possible on the opposite side, perpendicular to the fulcrum line, to resist rotation of the distal extension base.