Abstract
Purpose: A three-dimensional finite-element model of the mandible, including the temporomandibular joint (TMJ), was constructed in order to examine the influences of changes in the functional situation and anatomical morphology on TMJ loading. The purpose of this study was to investigate the influences of changes in the occlusal-supporting area and horizontal condylar angle on TMJ loading. Methods: Based on a juvenile human dry skull specimen, a numerical model of the mandible; including the TMJ, was developed. In this model, the ramus of mandible is excluded and the condyle and the body of mandible are connected with rigid elements. Contact elements allowed for slip and separation effects between the contact surface of the articular disk and the articular surfaces of the condyle and eminence. The magnitude and direction of the condylar displacement and the stress distributions on the articular disk during clenching were analyzed with respect to changes in the occlusal-supporting area and the horizontal condylar angle.
Results:
1. Under clenching conditions, stress distributions on the articular disk were demonstrated along the condyle, and stress was induced in the anterolateral areas of the articular disk.
2. Scenarios for the loss of posterior teeth and unilateral occlusion demonstrated increases in TMJ loading.
3. The increased horizontal condylar angle resulted in increased stress on the articular disk and a change in localization from the central area to anterolateral area. Conclusions: It was seen that changes in the occlusal-supporting area and horizontal condylar angle influence TMJ loading.
