Introduction
Diseases of the temporomandibular joint are not uncommon. Within Germany, disorders of the normal function of the temporomandibular joint are, in addition to the occurrence of carious defects, one of the most frequent abnormalities in the oral cavity. According to extensive studies, over 10 million citizens suffer from temporomandibular joint arthrosis.
The number of patients suffering from less conspicuous disorders of the temporomandibular joint far exceeds this number. In most cases, deficits in temporomandibular joint function manifest themselves at a very early stage in the affected patient through the occurrence of temporomandibular joint cracking, tension and pain in the chewing muscles, headaches and earaches or restrictions in the opening of the mouth. It is generally assumed that such problems of the temporomandibular joint are mostly caused by incorrect loading and mechanical wear of the joint surfaces consisting of cartilage.
However, there are also patients who develop such symptoms due to inflammatory or infectious causes. With increasing age, the risk of developing a disease of the jaw with clearly perceptible (and sometimes audible) clicking of the temporomandibular joint increases demonstrably. In addition, a possible genetic predisposition or heavy physical work also seems to play a decisive role in the development of temporomandibular joint diseases.
Anatomy
The temporomandibular joint (lat. Articulation temporo- mandibularis) represents a movable connection between the bony upper jaw (lat. Maxilla) and the lower jaw bone (lat.
Mandibula), in which the so-called mandibular fossa (lat. Fossa mandibularis) enters into direct contact with the head of the upper jaw (Caput mandibulae). While the upper jaw bone forms the rigid part of the temporomandibular joint, the lower jaw, which is essential for opening the mouth, is freely movable and clamped into the joint.
This bone connection is supported by numerous muscles (chewing muscles) and ligaments. To prevent the two bony structures of the temporomandibular joint from rubbing against each other, the head of the upper jaw and the mandibular fossa are separated by a movable part of cartilage (articular disc). The cartilage disc divides the temporomandibular joint into two functionally independent parts, the upper and lower joint space.
Sliding movements are mainly performed in the area of the upper joint section (upper joint gap). Rotational movements, on the other hand, take place mainly in the lower joint space. For chewing or speaking, however, it is by no means sufficient to perform one of these two movements separately. In these processes, both ranges of motion must be cleverly combined with each other. From this fact it can be deduced that combination movements (so-called turn-slide movements) can also be performed in the temporomandibular joint.
