Application of three dimensional model in treatment of superolateral dislocation of mandibular condyle

OBJECTIVE: To assess the application of three-dimensional jaw model in treatment of superolateral dislocation of condyle. METHODS: Nine patients with superolateral dislocation of condyle and symphyseal fractures were admitted in hospital from June 2008 to June 2013. Spiral CT scan on maxilla and mandible was performed，and three-dimensional jaw model was constructed with rapid prototyping technology. According to conditions of condylar superolateral dislocation model，the operation scheme was designed. The symphyseal fracture line was made and fracture was reduced on three-dimensional jaw model. Individualized prefabricated reconstructive titanium plate was made on symphyseal fracture model. Symphyseal fracture was replaced with individualized prefabricated mandibular reconstruction titanium plate according to occlusal relationship. At the same time，reduction of condylar superolateral dislocation was accomplished. RESULTS: Operations were successfully completed in 9 cases under guidance of three dimensional jaw model surgery. Operative incision was primarily healed，and occlusal relationship was restored. Postoperative CT scan showed that the locations of condyle in 9 cases were completely restored. Patients were followed-up for 6-28 months with a median of 18 months. The maximum of mouth opening was 3.1- 4.2 cm with a medians of 3.3 cm，and the occlusal relationship of all patients was normal after surgery. CONCLUSION: Three-dimensional jaw model can show complete status of condylar superolateral dislocation and symphyseal fracture. The model can accurately shape symphyseal reconstructive titanium plate and restore condylar superolateral dislocation during reductive surgery.