Mandibular Medial Osteotomy Modifications and Postoperative Stability

This study aims to evaluate and compare the effects of two different medial mandibular osteotomy modifications, namely the Hunsuck and Posnick techniques, on postoperative skeletal stability and relapse in patients undergoing orthognathic surgery.

Patients who meet the study eligibility criteria and are scheduled to undergo bilateral sagittal split ramus osteotomy (BSSO) as part of orthognathic surgery will be included. Depending on the medial mandibular osteotomy technique used, patients will be evaluated in two groups: those undergoing the Hunsuck modification and those undergoing the Posnick modification.

Preoperative and postoperative radiographic records will be evaluated to assess skeletal changes associated with each osteotomy technique. Postoperative skeletal stability will be assessed by comparing relevant mandibular and skeletal reference points and angular measurements between the preoperative, immediate postoperative, and follow-up imaging records. The amount and direction of postoperative skeletal relapse will be determined based on changes occurring during the follow-up period.

The primary objective is to determine whether the Hunsuck and Posnick modifications differ in terms of postoperative skeletal stability and relapse following orthognathic surgery. Secondary evaluations may include assessment of the magnitude and direction of mandibular positional changes and comparison of the radiographic outcomes between the two techniques.

The findings of this study may provide clinically relevant information regarding the influence of medial mandibular osteotomy design on postoperative skeletal stability and may help guide the selection of an appropriate osteotomy technique in orthognathic surgery.

Inclusion criteria

• Patients with an indication for orthognathic surgery who are planned to undergo bimaxillary orthognathic surgery.
• Patients who have undergone preoperative orthodontic treatment.
• Patients aged 18-65 years.

Exclusion criteria

• Patients who develop an unfavorable split (bad split) during surgery.
• Patients with cleft lip and palate, craniofacial syndromes, or a history of facial trauma.
• Patients who have previously undergone orthognathic surgery and require revision surgery.
• Patients whose computed tomography (CT) records are inadequate for the required measurements.