Postoperative assessment of mandibular angle reduction in facial feminization surgery

Facial feminization surgery is a key component of gender-affirming care, with mandibular angle reduction playing an essential role in creating a more feminine facial contour. This study evaluated the accuracy and effectiveness of using patient-specific cutting guides produced through virtual surgical planning and point-of-care 3D printing. Thirteen patients who underwent mandibular angle reduction at the University Hospital Basel were included. Preoperative CT or CBCT imaging was used to design and fabricate custom cutting guides, which were employed during surgery. Postoperative scans were assessed to determine changes in mandibular volume and surface distances, and to evaluate surgical accuracy. The results showed a significant average volume reduction of 1145.70 mm³ per mandibular angle, with a mean maximum surface distance of 8.04 mm. No significant differences in outcomes were found between the left and right sides. Osteotomies closely followed the planned resection lines, with mean deviations of 0.81 mm and maximum deviations of 1.79 mm. No intraoperative or postoperative complications occurred, and all patients experienced uneventful healing. These findings demonstrate that virtual planning combined with in-house 3D printing of cutting guides provides a safe, precise, and efficient method for mandibular contouring in facial feminization surgery, offering high surgical accuracy and cost-effective workflow integration.