<p>Objective: To evaluate, by magnetic resonance ımaging (MRI), theeffects of surgically assisted rapid maxillary expansion (SARME) onthe temporomandibular joint (TMJ) disc position.</p><p>Methods: Patients with maxillary transversial discrepeancies treatedSARME analyzed prospectively. The magnetic resonance imagingassessments of the TMJ were obtained before SARME operation andafter expansion process. Retention period, gender and presence ofwisdom teeth were the predictor variables. Disc position index (DPI)values were calculated and analyzed as an outcome variable.</p><p>Results: The study included 13 subjects (4 male, 9 female) with amean age of 19.5±2.3 years. After treatment there was excesschanging position seen in three articular disc relative the condyle inthree patient. Retention period, gender and presence of wisdom teethwere not significantly effected TMJ disc in terms of DPI values inmouth opened or closed position (p&gt;0.05).</p><p>Conclusion: According to our study TMJ disc position was noteffected significantly by SARME (p&gt;0.05)<br></p>