Clinical classification of maximal opening and closing movements

Opening and closing mandibular border movements of 250 subjects, 130 with clinical signs of TMJ pathosis and 120 normal subjects, were evaluated by measuring incisal interocclusal distance and recording mandibular movement on a tracking device. Both maximal opening and closing pathways were divided into initial and secondary phases, and were further classified into seven patterns on the basis of anomalous mandibular movements. Subjects with TMJ sounds tended to show mandibular deviations in the second phase, while those with tenderness to muscle palpation tended to show deviations in both phases. Subjects with bruxism demonstrated twice as many deviations in the second phase.