Persistent Temporomandibular Joint Abnormalities, Dysfunction Observed in Patients With Juvenile Idiopathic Arthritis

Persistence of comprehensive symptoms, dysfunctions, and damage of the temporomandibular joint (TMJ) are highly prevalent among patients with juvenile idiopathic arthritis (JIA) in the long-term, according to study results published in the Journal of Rheumatology. Compared with healthy control participants, patients with JIA were significantly more likely to present with orofacial pain, stiffness, and radiographic abnormalities at a 17-year follow-up.

Members of the Nordic JIA cohort were invited to participate in a follow-up study of TMJ involvement; the Nordic JIA cohort included children diagnosed with JIA between 1997 and 2000 from Denmark, Finland, Norway, and Sweden. At baseline and regular follow-up visits, the investigators assessed demographic data, overall disease activity, orofacial symptoms, and radiographic progression. Full-face cone-beam computed tomography (CBCT) was performed to measure condylar abnormalities. Patients with JIA were age-matched with healthy control participants, who also received orofacial examinations, not by CBCT. Logistic regression was performed to identify predictors of orofacial symptoms and condylar changes over follow-up, and descriptive statistics to assess the clinical characteristics and disease activity of all study participants.

Of the 420 eligible participants from the original JIA cohort, 265 (63.1%) were included in this study. Mean age of participants was 23.5±4.2 years, with a mean follow-up time from JIA onset to most recent orofacial examination of 17.3±1.3 years. The majority of patients were girls (70.2%). The control group had a similar mean age (23.6±2.9 years), but the distribution of sex was less skewed (52.5%).

In total, 87 patients with JIA (32.8%) reported ≥1 TMJ-related symptom at the 17-year follow-up. Orofacial pain, number of orofacial symptoms, TMJ-specific pain, morning stiffness, and chewing limitations were all significantly more common among patients vs control participants (P ≤.05). The mean maximal incisal opening was significantly lower among patients with JIA compared with the control participants (P <.001). Among patients who were assessed by CBCT (n=245), the investigators observed ≥1 abnormal radiologic TMJ feature in 60.8%, among whom bilateral TMJ deformities were indicated in 69.8%. Abnormal condylar findings were present in all JIA categories but most frequently among patients with rheumatoid factor-negative polyarticular JIA (76.5%). According to multivariate regression analysis, orofacial dysfunction at baseline predicted condylar deformities and erosions at follow-up. Treatment with biologics during the disease course and orofacial dysfunctions at the 17-year follow-up were significantly associated with a higher risk for TMJ deformity; however, enthesitis-related JIA was protective against condylar deformity. Age and sex did not significantly affect likelihood of TMJ abnormalities.

Study limitations included the fact that 37% of patients were lost to follow-up, and that no differences were observed in sex, disease activity at baseline, and JIA category, despite lower age at disease onset of the patient cohort,

While the association between biologics treatment and TMJ symptoms warrants further investigation, “We suggest including aspects of TMJ involvement in the general clinical decision making by including orofacial symptom and dysfunction assessment as an integrated part of general health assessment in JIA,” the investigated concluded.

Reference

Glerup M, Stoustrup P, Matzen LH, et al. Longterm outcomes of temporomandibular joints in juvenile idiopathic arthritis: 17 years of followup of a Nordic juvenile idiopathic arthritis cohort [published online September 15, 2019]. J Rheumatol. doi:10.3899/jrheum.190231