Clinical assessment of temporomandibular joint bone tissue destruction in rheumatoid arthritis

Purpose: To investigate the relation between temporomandibular joint (TMJ), pain and anterior open bite versus TMJ structional changes Materials and Methods: Sixty-four patients, 18 men and 46 female, with TMJ involvement of rheumatoid arthritis (RA) were included. 20 healthy patients were included as controls. A clinical examination performed regarding TMJ pain, tenderness to palpation and the degree of anterior open bite. A bilateral radiographic examination (tomography) of the TMJ was conducted and presence or absence of erosive changes was semiquantitively recorded in six regions in the temporal part and in six regions on the condyle of each TMJ. The sum of the left and the right side was used in the analysis Results: Anterior open bite was related to ongoing or resent structural changes in the TMJ, as indicated by the radiographic signs of erosions. Anterior open bite was also related to crepitus and TMJ pain. TMJ erosions, on the other hand, were only related to crepitus. A degree of 2 or more of anterior open bite is abnormal. Conculsion: This study indicates that the degree of anterior open bite, but not TMJ pain, is related to structional changes of the TMJ in RA, in turn indicating differences in inflammatory modulation of pain and tissue destuction. It seems that assessment of the degree of anterior open bite is of value for detection and monitoring of ongoing TMJ tissue destruction in RA.