Aim: The aim of the study was to assess possible correlations between the clinical parameters of temporomandibular joint (TMJ) arthritis and pathologic MRI findings of the TMJ in patients affected by juvenile idiopathic arthritis (JIA), and the effect of a functional orthodontic therapy on the evolution of TMJ disorders.
Materials and methods: A prospective clinical and nuclear magnetic resonance (NMR) investigation was conducted on a sample of 53 patients (41 female, 12 male) with JIA, treated for 24 months with an Andresen appliance. The involvement of TMJ was defined by clinical and radiological signs. NMR assessments were performed in closed and maximum opening mouth position before (T0) and at the end of functional orthodontic therapy (T1).
Results: Fifteen patients showed physical and radiologic TMJ abnormalities. Changes were not uniformly distributed among the different JIA subtypes. Patients with poliarticular JIA (≥5 peripheral joints affected) showed more destructive bony changes. No correlation existed between clinical symptoms and NMR alterations. Approximately one half of the patients experienced significant improvement of the TMJ and muscular pain using the Andresen appliance.
Conclusion: The prevalence of TMJ involvement in patients suffering of JIA, and the improvement of TMJ and muscular pain associated with the use of functional appliance found in the present study, suggest an alert for TMJ dysfunction in patients with JIA and demonstrate the utility of functional orthodontic therapy in preventing the morbidities associated with TMJ arthritis in JIA.