Surgical cutting and repositioning guides for minimally invasive orthognathic surgery: a retrospective comparative cohort study of bilateral sagittal split osteotomy.

Customized surgical guides may improve the accuracy of minimally invasive orthognathic surgery, particularly in facilitating the transfer of three-dimensional virtual surgical planning (3D-VSP) to the operative setting. This retrospective comparative cohort study included patients undergoing bimaxillary surgery with simultaneous genioplasty. Fifty consecutive patients were assessed for eligibility during the study period between January and July 2024. Fourteen were excluded (seven initial implementation phase; seven class III deformity), leaving 36 patients for final analysis. Patients were chronologically allocated into a control group (pre-implementation) and a study group (post-implementation). Intraoperative cone-beam computed tomography (CBCT) with cranial-base superimposition was used to assess surgical accuracy. The primary outcome was skeletal movement accuracy, defined as the discrepancy between planned 3D-VSP and intraoperative outcomes, assessed by superimposition of VSP and CBCT datasets. Secondary outcomes included translational and rotational deviations, landmark-specific discrepancies (mm) at the mandibular B-point, gonion, and ramus, and corticotomy angle deviation (degrees) to evaluate osteotomy accuracy. The guide-assisted group demonstrated significantly improved B-point accuracy (P = 0.001) and corticotomy angle precision (P = 0.012). Threshold-based accuracy outcomes also favored the guide-assisted group, while operative time did not differ significantly between groups. No predefined intraoperative complications were observed in either group. In-house customized surgical guides improved the intraoperative transfer accuracy of 3D-VSP in minimally invasive bilateral sagittal split osteotomy without increasing operative time.