Porcelain Margin Prep Guide
For Porcelain Fused To Metal Crowns

The Porcelain Margin can be an integral part of a premium restoration, maximizing esthetics and oral health. The porcelain margin helps avoid metal visibility, tissue discoloration and possible over-building of the gingiva.

PREPARATION NOTES " Where a porcelain margin is desired, the crown preparation must be either a 90 degree shoulder (preferred) or a deep chamfer (Figs.1 & 2). " All preparations should be smooth and display no sharp line angles. " As in all other fixed prosthodontic procedures, any undercuts must be blocked out on the die. " Axial reduction should be a minimum of 1.3 - 1.5 mm for porcelain (0.5 mm for metal lingual). (Fig. 3) " For porcelain margins; beveled margins, knife-edge margins, feather-edge margins, slice preparations and light chamfers should be avoided. " All margins must be clean and well recorded in the impression so that all margins on the dies are clearly visible.