The temporomandibular joint in rheumatoid arthritis.

The temporomandibular joint (TMJ) was investigated clinically and by orthopantomography in 110 patients with rheumatoid arthritis (RA) and in 73 control subjects. Clinical symptoms in the TMJ were established in 34 per cent of the RA patients and in 18 per cent of the controls. Radiographic abnormalities were found in 60 per cent of the RA patients compared with 15 per cent in the controls. No single radiographic abnormality was characteristic of joint involvement by RA. The most common radiologic features in RA patients were changes in the morphology of the condylar head and articular eminentia, marginal irregularities, reduced mobility, and an anterior position of the condylar head. No abnormalities were encountered in the early stage of the disease, which at least in part could be attributed to the inherent limitations of orthopantomography. The incidence of joint lesions increased with duration of the RA.