The influence of assisted mandibular movement on the incidence of nonworking tooth contact.

A total of 147 subjects were examined for nonworking tooth contacts. The subjects were instructed to voluntarily move their mandibles 2 mm laterally and surveyed for tooth contacts on the nonworking side. If no contact was present, moderate forces were applied to the angle of the mandible and the subjects were again surveyed for the same tooth contacts. This procedure was repeated on the opposite side to collect two units of data from each subject. Three significant findings were revealed in the study. 1. A significant number of sides (29.9%) and patients (43.5%) had nonworking contacts during voluntary movement. 2. The incidence of nonworking contact increased significantly (87.8% of the sides and 94.5% of the patients) when force was applied to the mandible. 3. With assisted movement, women exhibited a more significant increase (91.1% of the sides) in nonworking contact than did men (79.3% of the sides).