Porcelain Margin Preparation Guide
For Porcelain Fuse To Metal Crown
Make a margin line continuously and clearly.
Make an angle rounded smooth and no sharp edge.
1. The Crown preparation must be either 90 degree shoulder or 120 degree deep chamfer.
2. All preparation should be smooth and no sharp line angles.
3. In all fixed prosthodontic procedures, any undercuts must be blocked out on the die.
4. Axial reduction should be minimum of 1.3 - 1.5 mm for porcelain and .08 for metal lingual.
5. For porcelain margin, beveled margins knife-edge, slice preparation and light chamfers should be
6. All margins must be clean and well recorded in the impression so that all margins on the dies are clearly