Temporomandibular Joint Involvement in Juvenile Idiopathic Arthritis: Can Clinical Examination and Panoramic Radiography Predict MRI Findings?

Background/Objectives: Temporomandibular joint (TMJ) involvement is common in juvenile idiopathic arthritis (JIA) and may impair function and craniofacial growth. Although magnetic resonance imaging (MRI) is the preferred imaging modality, its routine use in children is limited by cost, examination time, and potential sedation requirements. This study evaluated the diagnostic performance of clinical examination and panoramic radiography (OPG) compared with MRI. Methods: Seventy patients with JIA (52 females; mean age 13.4 ± 2.8 years) underwent standardized TMJ assessment, OPG, and non-contrast enhanced MRI. A composite clinical score (0–7) was calculated based on muscle and TMJ tenderness, mandibular deviation, reduced maximum mouth opening and joint clicking. A score ≥3 was considered positive. MRI served as the reference standard, with TMJ involvement defined primarily by structural or functional abnormalities. Results: At least one clinical sign of TMJ involvement was observed in 41% of patients. MRI-detected TMJ involvement was significantly more frequent among patients with a clinical score ≥3 than among those with a score <3 (92.0% vs. 24.4%; p < 0.001). Clinical examination showed 67.6% sensitivity, 94.4% specificity, 92.0% positive predictive value (PPV), and 75.6% negative predictive value (NPV). OPG findings were positive in 85.3% of MRI-positive patients and negative in all MRI-negative patients (p < 0.001), corresponding to 85.3% sensitivity, 100% specificity, 100% PPV, and 87.8% NPV. Conclusions: Clinical examination and OPG may help identify patients with a higher likelihood of MRI-detected TMJ involvement who may benefit from further MRI evaluation.