Postoperative Positional and Dimensional Changes of Mandibular Canal after Bilateral Sagittal Split Set-Back Osteotomy.

Objective: This preliminary study was planned to provide information about preoperative mandibular canal (MC) position and the postoperative positional changes of MC and length in three dimensions, with the purpose of providing some assistance in reducing inferior alveolar neurosensory disturbance (IAND).

Methods: MC was examined on CBCT data using SimPlant Pro Standalone 13.0. MC locations were measured in all dimensions, with respect to mandibular bony borders.

Results: The results showed that MC is frequently located in the midthird of the ramus anteroposteriorly and superoinferiorly and in the midthird of the corpus superoinferiorly. Postoperatively, ramus width was increased, ramus length was decreased significantly, and MC was repositioned laterally and inferiorly. MC length was decreased on both sides, non-correlated with the set-back amounts.

Conclusion: Preoperative results may be beneficial for the prediction of MC position for surgeons, and postoperative results will be used for the following studies to correlate postoperative positional changes with IAND.