The temporomandibular joint in video motion--noninvasive image techniques to present the functional anatomy.

The presentation of the functional anatomy of the temporomandibular joint (TMJ) is involved with difficulties if dynamic aspects are to be of prime interest, and it should be demonstrated with the highest resolution. Usually noninvasive techniques like MRI and sonography are available for presenting functionality of the temporomandibular joint in video motion. Such images reflect the functional anatomy much better than single pictures of figures could do. In combination with computer aided records of the condyle movements the video motion of MR and sonographical images represent tools for better understanding the relationships between functional or dysfunctional patterns and the morphological or dysmorphological shape and structure of the temporomandibular joint. The possibilities of such tools will be explained and discussed in detail relating, in addition, to loading effects caused by transmitted occlusal pressure onto the joint compartments. If pressure occurs the condyle slides mainly more or less retrocranially whereas the articular disc takes up a more displaced position and a deformed shape. In a few extreme cases the disc prolapses out of the joint space. These video pictures offer new aspects for the diagnosis of the disc-condyle stability and can also be used for explicit educational programs on the complex dysfunction-dysmorphology-relationship of temporomandibular diseases.