Abstract
The difficulty in investigating masticatory movement is profound as seen in the fact that odontological research over approximately half a century has failed to provide definitive results. In order to investigate the masticatory function of the temporomandibular joint and the developmental mechanics of neuromuscular hypertonia of the masticatory muscles, a trace of the mandible body was made on a transparent plastic sheet from the right lateral view of the head. This method of observation provided a variety of information. Taking into consideration phenomena observed in clinical dentistry, “the masticatory function of the temporomandibular joint” and “the developmental mechanics of hypertonia of the masticatory muscles” were further observed.
