Rheumatoid arthritis and its implications in temporomandibular disorders.

Rheumatoid arthritis is known to afflict the temporomandibular joint (TMJ) with common symptoms including pain during function, tenderness on palpation, stiffness, and crepitus. New evidence suggests that metalloproteinases may be responsible for tissue changes that occur in rheumatoid arthritis. These enzymes are collagenase, gelatinase, and proteoglycanase. Antiinflammatory drugs are the first line of management for pain and inflammation in rheumatoid arthritis. This paper, however, suggests that because increased joint load is believed to cause a greater expression of destructive metalloproteinase, it is appropriate to assess even the asymptomatic temporomandibular joint and the muscles of mastication for early objective signs of dysfunction or discomfort. Interceptive management, by the use of load-reducing appliance therapy, may enable reduction of the expression of destructive metalloproteinase within the joint, thereby reducing joint destruction.