Occlusal Contact Area and Masticatory Movement of the Lateral Occlusal Position

Abstract

This study investigated the relationship between occlusal contact area (OCA) of the lateral position, masticatory movement path and masticatory rhythm.
Bite impressions of 17 healthy subjects were used to determine the OCA of less than 50 μm in thickness. Three mandibular positions, the intercuspal position (IP), and right and left lateral 1 mm positions from the IP were regulated with an altered extraoral Gothic arch tracer. Mandibular movement was recorded in the frontal plane during 10 strokes to obtain the mean masticatory rhythm and the mean angle of closing path using a Gnatho-hexagraph (GC, Tokyo, Japan). The results showed that changes of OCA occurred when the occlusal biting force increased the IP, the working side and the balancing side. The OCA of the working side and the balancing side 1 mm lateral from the IP showed a significant relationship according to the cusp angle. This relationship was observed in the case of light and strong bite forces. Occlusal contact of the balancing side occurred when occlusal force was increased. Therefore, it is recommended that during the final stage of occlusal adjustment, occlusal contact and cusp angle of the balancing side also need to be assessed.