Fixed partial dentures: tooth preparation principles, impressions
Prosthodontics and Crown and Bridge · Dental (BDS)
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Study notes
Why is a crown preparation tapered slightly instead of perfectly parallel? A slight taper (6–10°) lets the crown slide on and off during try-in and cementation without binding, while still providing enough frictional retention. Perfectly parallel walls would lock or create undercuts that block seating; excessive taper loses retention and the crown loosens. The taper window is the taught compromise between seatability and grip.
Related topics
- Complete dentures: diagnosis, treatment planning, impressions
- Complete dentures: jaw relations — vertical and centric
- Complete dentures: occlusion — balanced, lingualized; teeth arrangement
- Complete dentures: try-in, processing, insertion, post-insertion care
- Removable partial dentures: classification — Kennedy, Applegate
- Removable partial dentures: components — clasps, rests, connectors