[Application of the thermoelastic stress imaging method to prosthodontics. (2) Basic study of the stress field of artificial molar teeth, in which the existence of saliva was considered].

A basic study was conducted utilizing a thermoelastic stress imaging method for stress analysis of model of simplified artificial molars based on an interocclusal contact relationship. This involved examining the effect of artificial saliva application on a stress field in a situation where occlusal pressure was applied in a dynamic sliding movement. As a result, the following conclusions were obtained. 1. The thermoelastic stress imaging method allowed the stress field to be determined artificial saliva application at distributed load due to plane contact in dynamic sliding movement. 2. Compared with the case of non-saliva application, in a squaremodel having a sliding movement and to which artificial saliva was applied, the pattern of the high compressive stress area was found to be a circle or an ellipsoid. This showed a slight dispersion trend at 10 degrees, with the contact plane as the boundary, and the dispersion of stress concentration began to become clearer at 20; stress concentration on the contact plane tended to disappear at 30 degrees, and sliding was conspicuous and determination impossible at 45 degrees. 3. Results showed that 10 degrees was a transition angle at which a different aspect was shown, representing a trend in a stress field pattern change accompanying an increase in the facet bevel angle when artificial saliva was applied. 4. From the results of stress analysis using the square-shape sliding movement model to which artificial saliva was applied, 10 degrees to 20 degrees of facet bevel of artificial molars was considered preferable in consideration of the presence of saliva.