Randomized Clinical Trial of the Accuracy of Patient-Specific Implants versus CAD/CAM Splints in Orthognathic Surgery

Background: The maxilla position is essential for the aesthetic and functional outcomes of orthognathic surgery. Previous studies demonstrated the advantages of patient-specific implants in orthognathic surgery. However, more data are needed to confirm the superiority of patient-specific implants over surgical splints created with computer-aided design/computer-aided manufacturing (CAD/CAM). This randomized controlled trial aimed to compare the accuracy of patient-specific implants and CAD/CAM splints for maxilla repositioning in orthognathic surgery. Methods: Patients (n = 64) who required orthognathic surgery were randomly assigned to use either patient-specific implants (patient-specific implant group) or CAD/CAM surgical splints (splint group) to reposition the maxilla. The outcome evaluation was completed by comparing virtual plans with actual results. The primary outcome was the discrepancies of the centroid position of the maxilla. Other translation and orientation discrepancies of the maxilla were also assessed. Results: The authors analyzed 27 patients in the patient-specific implant group and 31 in the splint group. The maxilla position discrepancy was 1.41 +/- 0.58 mm in the patient-specific implant group and 2.20 +/- 0.94 mm in the splint group; the between-group difference was significant (p < 0.001). For the patient-specific implant group, the largest translation discrepancy was 1.02 +/- 0.66 mm in the anteroposterior direction, and the largest orientation discrepancy was 1.85 +/- 1.42 degrees in pitch. For the splint group, the largest translation discrepancy was 1.23 +/- 0.93 mm in the mediolateral direction, and the largest orientation discrepancy was 1.72 +/- 1.56 degrees in pitch. Conclusion: The result showed that using patient-specific implants in orthognathic surgery resulted in a more accurate maxilla position than CAD/CAM surgical splints.