Temporomandibular involvement in children and adolescents with juvenile idiopathic arthritis: a 2-year prospective cohort study

This study aimed to clinically evaluate temporomandibular joint (TMJ) involvement in juvenile idiopathic arthritis (JIA) and the ability to identify and/or predict development of TMJ-deformities over time using cone beam computed tomography (CBCT). The predictive value of self-reported TMJ pain was also assessed. A prospective longitudinal cohort study comprising 54 children with JIA, 39 girls and 15 boys, was performed. All children had active disease at baseline, 50% with the subtype oligoarthritis. Repeated clinical orofacial and CBCT examinations were performed over a two-year period. At baseline, 39% had radiographic TMJ deformities (24% unilateral, 15% bilateral), at 2-year follow-up, 42% (p > 0.05). Both progressing and improving TMJ deformities were observed. An association was found between TMJ-deformities and self-reported TMJ pain at baseline (p = 0.01). Maximum unassisted mouth opening (MUO) was smaller for children with TMJ-deformities (p < 0.05). The prevalence of palpatory muscle pain was high (48-59%) but not predictive of development of TMJ-deformities. TMJ noises increased over time and crepitations were associated with TMJ-deformities (p < 0.05). In conclusion, in children with JIA, self-reported TMJ pain and dysfunction were common and predictive of TMJ deformities. TMJ deformities were associated with smaller MUO and palpatory TMJ pain as well as crepitations.