Do patient-specific cutting guides and plates improve the accuracy of maxillary repositioning in hemifacial microsomia?

The aim of this retrospective study was to use computer-aided design and manufacturing (CAD/CAM) patient-specific plates and cutting guides for the waferless positioning and fixation of the maxilla after bimaxillary osteotomies in cases of hemifacial microsomia with condylar dysplasia or absence of the temporomandibular joint (TMJ), and to compare the results with the CAD/CAM fabricated surgical wafer by 3-dimensional analysis. Eighteen patients were selected from the hospital database, preoperative surgical planning and simulation were done on 3-dimensional computed tomographic models for all patients, and they were divided into Group I - in which CAD/CAM patient-specific cutting guides and plates were used; and Group II - in which CAD/CAM fabricated surgical wafers were used. Finally, the outcome was evaluated by comparing planned with postoperative outcomes. The largest discrepancies of the Le Fort I segment were 0.50 (0.18) mm in the anteroposterior direction and 0.82 (0.60)° in the yaw orientation with Group I. The largest discrepancies of the Le Fort I segment were 1.32 (1.40) mm in superioinferior direction and 8.48 (7.73)° in the yaw orientation with Group II. The CAD/CAM patient-specific cutting guides and plates proved to be reliable and have great value in improving the accuracy in repositioning the Le Fort I segment and in the efficacy of orthognathic treatment of hemifacial microsomia with condylar dysplasia or no TMJ. The CAD/CAM patient-specific cutting guides and plates are therefore a useful alternative to the wafer technique.
(Copyright © 2020. Published by Elsevier Ltd.)