TMJ involvement prevalent in adults with JIA

Clinically established temporomandibular joint (TMJ) involvement occurs frequently in adults with juvenile idiopathic arthritis (JIA), which suggests the need for awareness of TMJ problems in this population, according to a study.

A team of researchers compared the TMJ screening protocol, mandibular range of motion (MROM), and anterior maximum voluntary bite force (AMVBF) between adults with JIA and healthy control participants. They also constructed unadjusted and adjusted models with corrections for sex and disease duration for active maximum interincisal mouth opening (AMIO) and AMVBF.

Overall, 100 adults with JIA and 59 healthy controls participated in this study. Clinically established TMJ involvement was present in 56 percent of adults with JIA. The MROM variable most reduced by TMJ involvement was AMIO, which was 8.8-mm (95 percent confidence interval [CI], ‒11.40 to ‒6.12; p<0.001) less in adults with JIA with TMJ involvement compared to those without.

AMIO did not differ between healthy controls and adults with JIA without TMJ involvement (‒2.52, 95 percent CI, ‒5.13 to 0.10; p=0.06). Higher AMIO was more common among male adults, while lower AMIO was associated with disease duration. Of note, collinearity was observed between the subtype prebiologic era and disease duration.

Additionally, no difference in AMVBF was seen between adults with JIA and healthy controls.

“TMJ involvement negatively influenced AMIO and should therefore be part of the TMJ screening in adults with JIA,” the researchers said. “AMVBF seems to have less utility for TMJ screening in adult populations.”