Effect of altered canine guidance on condylar movement during laterotrusion.

The purpose of this study was to investigate the effect of an altered inclination of the canine guidance on the pattern of the condylar movements during laterotrusion.The inclination of the canine guidance was steepened approximately 10 degrees by attaching a metal overlay to the lingual surface of the maxillary working-side canine. The laterotrusive movements of 20 young adults were measured using a three-dimensional mandibular movement analyzing system before and after alteration of the canine guidance. The difference between anterior, lateral, and inferior components of the working- and nonworking-side condylar movements, the Bennett angle, and the sagittal inclination of the nonworking-side condylar path before and after steepening of the canine guidance was evaluated by a paired t test.After the canine guidance was steepened, the working-side condyle moved even more anteriorly and inferiorly. In contrast, little change was found in the direction and the amount of the nonworking-side condylar movement.The results of this study suggest that there is a relationship between the steepness of canine guidance and the pattern of the working-side condylar movement. but not between the steepness of the canine guidance and the pattern of the nonworking-side condylar movement.