The influence of open disc repositioning surgery on the internal derangement of the contralateral temporomandibular joint: a prospective study of 96 patients.

Objective: To assess the influence of unilateral open disc repositioning surgery (ODRS) of the temporomandibular joint (TMJ) on the internal derangement (ID) of the contralateral joint.

Methods: Patients with bilateral ID of TMJ who underwent unilateral ODRS were enrolled and followed-up for one year. They were divided into two groups based on the contralateral disease: the anterior disc displacement with reduction (ADDWR) and without reduction (ADDWoR). Postoperative evaluation included clinical and MRI evaluation. Indices measured were unilateral intermaxillary distance (UID), visual analogue scale (VAS), disc length (DL), condylar height (CH), and disc-condyle angle (DCA). Paired t tests were used to compare the clinical and MRI indices between different time points.

Results: Ninety-six patients were enrolled, including 47 in the ADDWR group and 49 in the ADDWoR group. One-year post-surgery, ODRS led to significant increases in MMO, DL, and CH, and decrease in VAS and DCA on the operated side (P < 0.05). In ADDWR group, UID, DL, and CH increased significantly, and VAS decreased (P < 0.05), with no significant change in DCA (P > 0.05). In ADDWoR group, clinical and MRI variables worsened slightly, except for UID, which remained unchanged (P > 0.05).

Conclusions: ODRS is a promising method for correcting TMJ ID and may improve condition of ADDWR and decrease progress of ADDWoR at the contralateral joint. Preoperative bilateral TMJ evaluation is essential for better outcomes.

Clinical relevance: ODRS can effectively treat TMJ ID and produce adaptive changes in the contralateral ID, for which continuous monitoring of the contralateral joint is essential.