The influences of shoulder porcelain length on the stress distribution of metal-ceramic crowns

OBJECTIVE: To analyze the stress distribution induced by simulated intra-oral loads on ceramometal crowns with different length of shoulder porcelain in labial margins. METHODS: Eighteen two-dimensional finite element models of the maxillary central incisor restored with ceramometal crowns were constructed which were designed with different labial terminal locations of metal coping. Different coping alloys and marginal designs were employed in the crown models. The stresses of porcelain veneers and adhesive layers in all models were estimated with different loading locations and angles. RESULTS: Although coping alloys and marginal designs were different, the labial terminal locations of metal coping had no influence on the stress distribution of porcelain veneers and adhesive layers. CONCLUSION: The coping design of short labial margin to add the length of shoulder porcelain of ceramometal restorations can be used clinically.