Average Three-Dimensional Skeletofacial Model as a Template for Bone Repositioning during Virtual Orthognathic Surgery

Abstract

Background: Virtual planning has revolutionized orthognathic surgery. This study presents a computer-assisted method for constructing average three-dimensional skeletofacial models that can be applied as templates for surgical planning for maxillomandibular repositioning. Methods: The authors used the images of 60 individuals (30 women and 30 men) who had never undergone orthognathic surgery to construct an average three-dimensional skeletofacial model for male participants and one for female participants. The authors validated the accuracy of the newly developed skeletofacial models by comparing their images with 30 surgical simulation images (ie, skulls) that had been created using three-dimensional cephalometric normative data. The comparison was conducted by superimposing surgical simulation images created using the authors’ models with the previously created images to analyze their differences, particularly differences in the jawbone position. Results: For all participants, the authors compared the jaw position in the surgical simulation images created using the authors’ average three-dimensional skeletofacial models with that in the images created using three-dimensional cephalometric normative data. The results revealed that the planned maxillary and mandibular positions were similar in both images and that the differences between all facial landmarks were less than 1 mm, except for one dental position. Most studies have reported less than 2 mm to be the success criterion for the distance difference between planned and outcome images; thus, the authors’ data indicate high consistency between the images in terms of jawbone position. Conclusion: The authors’ average three-dimensional skeletofacial models provide an innovative template-assisted orthognathic surgery planning modality that can enhance the fully digital workflow for virtual orthognathic surgical planning. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.