[Histological studies of the morphological relationship of the lateral pterygoid muscle to the articular disk in the human temporomandibular joint].

Abstract

The biomechanical process which lead to the development of cracking sounds in the temporomandibular joints have received contradictory treatment in the literature. Most of the authors regard consider the cracking sounds to be caused by mechanical friction produced in translational movements of the condylus. According to this hypothesis the discus articularis which is dislocated in an anterior direction active pulling of the lateral pterygoid muscle, is regarded as being a mechanical obstacle. The morphological relationships however, between the lateral pterygoid muscle and the discus articularis are unclear. Our histomorphological investigations of 16 human temporomandibular joint samples from fresh cadavers of victims of accidental death revealed evidence that in the majority of cases a tendon connected the upper head of the lateral pterygoid muscle with the discus articularis. This would suggest that an anterior dislocation of the discus, resulting from an active pulling movement of the lateral pterygoid muscle, cannot be ruled out as a possible morphological cause for cracking sounds.