UCSF

ABSTRACT

Introduction: Cone beam computed tomography (CBCT) technology has many known benefits in diagnosis and treatment planning for both orthodontics and oral surgery, but systems to translate these benefits directly into patient treatment are still early in development. The purpose of this study is to define a protocol that incorporates multiple commercially available technologies into a patient's orthognathic surgery treatment, and to evaluate the accuracy in which a clinician can utilize this protocol to produce an intended result for that patient

Methods and Materials: Presurgical CBCT scans of 14 patients who had previously undergone orthognathic surgery (maxillary LeFort I osteotomy, mandibular bilateral sagittal split osteotomy (BSSO), or both) were segmented to isolate their jaws for independent manipulation. High resolution 3D images (Motion View Software, LLC, Chattanooga, TN) of the patient's dentition were then superimposed onto the segmented DICOM, and virtual surgery was performed using each patient's plaster-model surgery set-up as a guide and the Dolphin 11.7 software (Chatsworth, CA). Virtual splints were then designed and processed into tangible objects using computer aided design (CAD/CAM) printing technology. The difference in mandibular-maxillary relationship defined by the virtually designed splints compared to traditionally designed splints, was measured by calculating the distance between three mandibular fiducials, after superimposing CBCT scans of models mounted using each splint.

Results: Mean linear differences were found to be less than 1mm +/- SD in all dimensions

Conclusions: Virtual simulation of orthognathic surgery coupled to steriolithographic surgical splint generation is reliable, efficient, and potentially accurate to within 1mm of actual procedure outcomes.