A Sequential Study of the Condylar Position Deviation of the Reconstruction Plate for Mandible

Accurate reconstruction of the condylar process is essential when mandibular resection involves the condyle. To prevent postoperative displacement, intraoperative ligation of the reconstructed condyle to the preserved articular disc was performed. This study evaluated postoperative displacement of the reconstructed condyle. Twenty-three patients who underwent hemi-mandibulectomy and reconstruction using titanium plates between April 2001 and July 2023. Fifteen patients underwent ligation of the reconstructed condyle to the articular disc (ligation group), and 8 patients did not (nonligation group). Sequential displacement of the reconstructed condyle was evaluated using CT at 1 month and 1 year postoperatively. The mean displacement in the superior-inferior direction was upward, measuring 1.3 mm in the ligation group and 2.3 mm in the nonligation group. In the anterior-posterior direction, the mean displacement was 0.4 mm backward in the ligation group and 0.5 mm forward in the nonligation group. In the internal-external direction, the mean displacement was 0.3 mm outward in the ligation group and 0.3 mm inward in the nonligation group. No significant difference was observed in any direction. Pre- and postoperative changes in mouth opening showed a mean increase of 13.0 mm in the ligation group and 5.6 mm in the nonligation group, although there was no significant difference. These findings suggest that there is no significant functional difference between the ligation and nonligation groups. However, ligating the reconstructed condyle to the articular disc may have potential advantages in preventing dislocation, avoiding cranial base perforation of the plate, and reducing the risk of postoperative trismus.