Prospective outcome analysis of total replacement of the temporomandibular joint with the TMJ Concepts system in patients with inflammatory arthritic diseases.

We report the outcomes of patients with rheumatoid arthritis, psoriatic arthritis, or ankylosing spondylitis, who had total replacement of the temporomandibular joint (TMJ) using the TMJ Concepts system between 2005 and 2014. We prospectively measured mouth opening (mm), and pain and dietary function (visual analogue scale (VAS), 1 - 100) before operation, and at 6 weeks, 6 months, one year, and beyond. Forty-six joints were replaced in 26 patients (mean age 40, range 16 - 71), 22 of whom were female. Most had rheumatoid (n=17) or psoriatic arthritis (n=7). At one year the mean (SD) pain scores had fallen from 55 (36) to 2 (7) on the left, and from 62 (31) to 2 (5) on the right (p<0.001). Mean (SD) scores for dietary function had increased from 48(25) to 95(9) (p<0.001), and mouth opening had increased from a mean (SD) of 23(10) mm to 35(5) mm (p<0.001). The joints dislocated during the operation in 5 patients, and 4 had temporary weakness of the facial nerve. Outcomes after replacement of the TMJ with the TMJ Concepts system were good in patients with inflammatory arthritis, which further validates the procedure, as damage to the joint is severe in this group.