Correspondency between Path of Chewing Movement and Lateral Border Movement

Mandibular movement occurs during chewing, speech and swallowing functionally or during bruxism and clenching parafunctionally. Further, the occlusal facet is caused by functional mandibular movement and parafunctional mandibular movement. However, it is not defined to what extent the occlusal facet is within the range of functional mandibular movement. The purpose of this study was to examine the extent of functional tooth grinding in chewing mandibular movement. One hundred dental students were used in this study, and the portion of correspondence of path of chewing and lateral border movement was measured using Sirognathograph Analyzing System III. As a result, some subjects had a large corresponding portion of path of chewing mandibular movement and path of lateral border movement. The extent of functional tooth grinding in chewing movement has been considered to be small near the centric occlusion, however, the results suggested that a large portion of the grinding surface was used by functional mandibular movement.