[Finite element stress analysis of ceramics crown on premolar. Relation between ceramics materials and abutment...

This investigation was carried out to evaluate the alteration of stress distribution on ceramics crowns by each combination of ceramics crown materials and abutment materials. Analyzing the stress distribution by the finite element methods, a two-dimensional model of jacket crown preparation was designed on lower first premolar, and restored it by ceramics crown. Under four loading conditions, the tensile stress distributions on the ceramics crown were analyzed to evaluate the relations between three kinds of ceramics crown, which were an aluminous porcelain jacket crown, a feldspathic porcelain jacket crown and an Olympus castable ceramics (O.C.C.) crown, and three kinds of abutment which were a natural tooth, a gold cast core and a composite resin core. And following results were obtained: 1. When the abutment was a natural tooth, the tensile stresses were apt to occur all over the ceramics crown and these magnitude were increased in porportion to the height of Young's modulus of the ceramics materials. 2. When the abutment was a gold cast core or a composite resin core, the tensile stresses were produced only at the loading side of the ceramics crown, and the magnitude of stress were little affected by the type of core materials.