Metal-Ceramic Crown Prep: Guide to Precision and Aesthetics

Описание: Here’s a brief overview of metal-ceramic crown preparation:

1. Tooth Reduction:
Occlusal Surfaces: Reduce the occlusal surface by 1.5-2.0 mm to ensure sufficient space for the metal and ceramic.
Axial Surfaces: Reduce the axial surfaces by 1.2-1.5 mm. Ensure a consistent reduction to allow for uniform thickness of the crown.
2. Margin Design:
Facial/Buccal Margins: Create a shoulder or deep chamfer margin (about 1.0-1.5 mm) to accommodate the porcelain.
Lingual Margin: A chamfer margin of about 0.5 mm can be sufficient if metal coverage is planned for the lingual surface.
3. Taper: Ensure a slight taper of 4-8 degrees for the axial walls to allow for proper seating of the crown.
4. Smooth Edges: Round off any sharp corners or edges to minimize stress concentration and avoid fracture of the porcelain.
5. Avoid Undercuts: Make sure the preparation is free of undercuts and has a smooth, continuous outline.

This preparation ensures a good fit and aesthetic outcome for metal-ceramic crowns.