Is technical difficulty associated with the accuracy of patient-specific implants for maxillary repositioning in...

The use of patient-specific implants (PSIs) in minimally invasive orthognathic surgery remains limited due to concerns about technical difficulty and restricted intraoperative exposure. Whether increasing maxillary movement technical difficulty compromises the accuracy of PSI-assisted minimally invasive surgery remains unclear. This retrospective cohort study evaluated the accuracy of maxillary repositioning using PSIs in minimally invasive bimaxillary orthognathic surgery and its relationship to technical difficulty. Consecutive patients treated at the University of Texas Health San Antonio between June 2023 and September 2025 were included if they underwent bimaxillary minimally invasive orthognathic surgery with complete preoperative and postoperative cone-beam computed tomography records. Patients with craniofacial syndromes, comorbidities affecting postsurgical healing, or those undergoing single-jaw surgery were excluded. Technical difficulty was defined by the presence of maxillary advancement >7 mm, maxillary segmentation, or posterior maxillary impaction >1.5 mm. Accuracy was measured as the root mean square linear discrepancy between planned and postoperative maxillary positions. Demographic characteristics and malocclusion type were recorded as covariates. Thirty-six patients were included, with a mean age of 27 years. Comparisons were made across advancement magnitude, segmentation status, and posterior impaction. No statistically significant differences in root mean square discrepancies were observed across landmarks or axes after correction for multiple comparisons, with the lowest observed probability value being 0.02. These findings demonstrate that PSI-assisted minimally invasive orthognathic surgery achieves clinically acceptable accuracy across varying levels of technical difficulty, supporting its reliable use even in technically demanding cases.