Prosthodontics (Fixed, Removable, Implant-Supported)
What this domain tests
Fixed, removable, and implant prosthodontics are examined together because the board wants to see whether you can choose a prosthesis from the pattern of tooth loss, periodontal prognosis, bone, occlusion, and patient factors, then execute the design.
Core rules
- Crown preparation: 1.5-2 mm occlusal reduction, 1-1.5 mm axial reduction, 6-10 degrees convergence, supragingival margins where possible, and a finish line matched to material.
- Ferrule: at least 1.5-2 mm of sound axial dentine for any post-retained crown.
- Impression: vinyl polysiloxane with light-body syringed around margins in a rigid tray; polyether when moisture control is difficult.
- Removable partial denture: survey the cast; place rests, guide planes, and reciprocal elements; assign Kennedy class only after all extractions; Applegate's rules decide which teeth count.
- Major connector: maxillary strap or ring, mandibular lingual plate or bar; keep it clear of the gingival margin.
- Implants: screw retention for retrievability and cement-free margins; cement retention for corrected angulation; cleansable contours and no submucosal cement.
- Occlusion: even contacts in centric relation, no fremitus, mutually protected or group function.
Worked example
A 55-year-old is missing 16, 17 and 26; 24 has a 6-mm pocket and grade II mobility. Reasoning: do not finalise the Kennedy classification until the periodontal decision on 24 is made. If 24 is retained, the arch is Kennedy Class II modification 1; if 24 is lost, it becomes Class I. The design therefore starts with periodontal treatment and a provisional decision, not with a cast framework.
Traps
Classifying before extractions; skipping the survey; shallow rests; overcontoured connectors; ignoring vertical dimension.