Does orthognathic surgery affect mandibular condyle position? A retrospective study.

Purpose: The aim of this study is to analyze mandibular condyle position changes after bilateral sagittal split osteotomy (BSSO) and bimaxillary orthognathic surgery in patients operated at a single department by two surgeons in 2013-2022. Compared were groups of mandibular advancement vs setback and bimaxillary vs BSSO.

Methods: Ninety-nine subjects were included. Inclusion criteria were patients who underwent one of the BSSO or bimaxillary surgery and had CT scans performed before and after surgery. Preoperative CT scans were performed 1 day before surgery and postoperative CT scans 6-12 months afterwards. Changes in mandibular condyle position were measured in axial and sagittal planes.

Results: CT condylar position measurements indicated significant postoperative changes in AB angle bilaterally (p =  < 0.001). In mandibular advancement and setback comparison, values were significantly lower in ABL angle values in the setback group (p = 0.011326) and significantly higher in FDR in the advancement group (p = 0.005795). There were no statistically significant changes found in BSSO and bimaxillary group comparison.

Conclusion: Within the limitations of this study, it can be concluded that orthognathic surgery does have a moderate effect on position of the condyles, especially condylar rotation in transversal axis.