The effect of a functional appliance in the management of temporomandibular joint disorders in patients with juvenile idiopathic arthritis.

BACKGROUND Patients affected by juvenile idiopathic arthritis (JIA) may have several craniofacial growth disturbances and involvements at the temporomandibular joint (TMJ). The objectives of the present study were to evaluate the clinical effectiveness of functional therapy used to reduce asymmetry of mandibular growth and TMJ disorder in patients with JIA. METHODS By a retrospective longitudinal design, a cohort of 54 patients with JIA (mean age, 13.2±3.7 years; range, 5-17.7 years) and with TMJ involvements was enrolled in the study. Each patient, following the collection of clinical parameters, was treated for 24 months with a functional appliance individually customized by acrylic resin and resilient stainless steel with posterior and anterior metallic bite planes preventing the teeth from intercuspal contact. To evaluate differences before (T0) and after therapy (T1) of the clinical TMJ parameters, the statistical analysis by the χ2 Test was performed. RESULTS All the patients completed successfully the study. In patients with JIA, the use of a functional appliance determined a statistically significant difference of the pain during jaw movement, maximal mouth opening, TMJ sounds and crepitations (P<0.001) and TMJ click, significantly reduced at T1 (P<0.05). CONCLUSIONS The use of an orthodontic functional appliance determined a significant improvement, at 24 months, in many TMJ signs and symptoms in patients affected by JIA and with TMJ disorders. This study suggests that children and adolescents with JIA which presented either unilateral or bilateral moderate to severe TMJ involvement, if not treated, should be develop severe disturbances during growing.