The Use of Software Systems for Visualized Treatment Objectives in Orthognatic Surgery

Maxillomandibular harmony constitutes a major component of the ideal facial aesthetics. Improvement of facial aesthetics is one of the main reasons that patients request surgical correction of dentofacial deformities. Orthognathic surgery enables the correction of dentofacial skeletal or occlusal discrepancies. The need for this type of surgery has increased recently, as more adult patients are seeking orthodontic treatment (Nattrass & Sandy, 1995). Orthognathic surgery differs from other procedures of maxillofacial surgery procedures in a way that, the esthetic and psychosocial impact plays an important role in the patient perception of a successful treatment outcome. Therefore, a satisfying outcome of orthognathic surgery includes not only the decisive surgical technique and intermaxillary correction but also the accomplishment of the aesthetic goals that are successful to both patients and professionals (Sarver et al., 1988; Sarver & Johnston, 1990; Proffit & White, 1991). However, the concept of the ideal result is rather subjective and mainly determined by the consequency between the patient expectations and the actual result. Without a visual reference, it is hard for the patients to visualize the outcomes of the surgical procedures and to contribute to the treatment plan in the preoperative planning session (Turpin, 1995; Cunningham et al.1995). In this manner, visualized treatment objectives (VTO) are important predictive tools to interpret the patients’ perspectives of esthetics and to give an acceptable preview of the result. Furthermore, these VTOs facilitate the communication between the treatment team and the patient as well as provide guidance to the desired result. They also determine the need for bimaxillary versus single-jaw procedures and whether adjunctive treatments including rhinoplasty, genioplasty, liposuction or augmentation are necessary. Lateral cephalometric radiographs are commonly used to predict the surgical treatment outcomes. Visualized treatment prediction began with manual profile predictions. Tracing overlay approach or using templates are the two methods for profile prediction by pencil drawing. Tracing overlay approach involves manual repositoning of the overlaid tracings and is limited to simulate the effects of mandibular surgeries. In this method, cephalometric film is traced including all teeth with their occlusal surfaces on an acetate paper. Subsequently, the structures that will not be moved by mandibular surgery are traced over the original tracing with a new sheet of acetate paper. After sliding the overlay tracing so that the mandibular teeth can be seen in their desired postsurgical position, lower teeth and O pe n A cc es s D at ab as e w w w .ite ch on lin e. co m