Resorption of the temporomandibular condylar bone according to subtypes ofjuvenile chronic arthritis

Objective. To evaluate the relative impact of sex, type of onset, course of disease. age at onset, duration of disease and status of HLA-B27, antinucl ear antibodies (ANA), and rheumatoid factor on the risk of developing a con dylar erosion. Methods. Condylar changes of the temporomandibular joint (TMJ) were diagnos ed on orthopantomograms from 169 consecutive patients with juvenile chronic arthritis (JCA). A multiple regression analysis was applied to establish t he relative weight of the independent variables affecting the severity of t he condylar erosion. Results. It was found that 62.1% of the patients exhibited condylar resorpt ion. The highest prevalence was seen in children with a polyarticular onset or course of disease and early age at onset and severe resorption was also frequent in these groups. Patients with positive ANA also had a high preva lence but with a mild degree of resorption. In contrast, HLA-B27 positive p atients had a lower risk of TMJ involvement and resorptive changes of the c ondyle. Conclusion. Polyarticular and early onset arthritis are associated with a h igh risk for TMJ involvement and a severe condylar bone loss can be expecte d. ANA positive patients have a high prevalence. and B27 positive patients have a low prevalence of TMJ arthritis but in both subgroups, the outcome o f the bone resorptive process is mild.