Prior to the evaluation of the tensile adhesive strength of dental porcelain to castable glass ceramic, stress distribution was analyzed to determine the configuration of the tensile test pieces, by using the photoelastic stress analysis method. On the assumption that 3 type tensile test pieces of dental porcelain baked on castable glass ceramics, 3 photoelastic test models consisting of two layers were made of epoxy resin. A 2 kgf tensile load was added to each model, and the stress was maintained. The stress distribution of the median section was analyzed.
The results were as follows:
(1) The tensile stress was observed at the castable glass ceramic-porcelain interface of all test models.
(2) Stress concentration effects were significant at the periphery of castable glass ceramic-porcelain interface in two of 3 test models.
(3) Uniform tensile stress was observed at the castable glass ceramic-porcelain interface in only one of 3 test models.
