Influence of TMJ dysfunction on Bennett movement as recorded by a modified pantograph. Part I: Literature review

This review has pointed out the difficulties in studying the lateral side shift of the mandible (Bennett movement) as well as the many contradictory results that have evolved from investigations. Based on the studies reported, it seems reasonable to conclude that Bennett movement accompanies most subject's lateral jaw movements, but its amount and "timing" varies between individuals and may be influenced by muscle incoordination and TMJ dysfunction. Furthermore, the axis around which all lateral movements occur may be oblique rather than vertical and perpendicular to the subject's hinge axis. The importance of Bennett movement has often been emphasized. Disagreement and controversy still exist regarding (1) the immutability of its magnitude throughout the occlusal therapy and (2) the possible relationship between TMJ dysfunction and Bennett movement. A clinical study has been completed and will be reported in subsequent articles to give insight into the possible influence of the neuromusculature on the lateral side shift of the mandible.