A novel method of computer aided orthognathic surgery using individual CAD/CAM templates: a combination of osteotomy and repositioning guides

Abstract

The maxilla is usually positioned during orthognathic surgery using surgical splints, which has many limitations. In this preliminary study we present a new computer-aided design and manufacture (CAD/CAM) template to guide the osteotomy and the repositioning, and illustrate its feasibility and validity. Six patients with dental maxillofacial deformities were studied. The design of the templates was based on three-dimensional surgical planning, including the Le Fort osteotomy and the repositioning of the maxilla, and were made using a three-dimensional printing technique. Two parts of the templates, respectively, guided the osteotomy and repositioned the maxilla during operation. The traditional occlusal splint was used to achieve the final occlusion with the mandible in the expected position. Postoperative measurements were made between maxillary hard tissue landmarks, relative to reference planes based on computed tomographic (CT) data. The results of the measurements were analysed and compared with the virtual plan. The preliminary results showed that we achieved clinically acceptable precision for the position of the maxilla (<1.0mm). Preoperative preparation time was reduced to about 145min. All patients were satisfied with the aesthetic results. Our CAD/CAM templates provide a reliable method for transfer of maxillary surgical planning, which may be a useful alternative to the intermediate splint technique. Our technique does not require traditional model surgery, scanning of dental casts, or recording of the CAD/CAM splint.