Young-Chea Roh1, Sang-Hun Shin1, Seong-Sik Kim2, George K Sandor3, Yong-Deok Kim4. 1. Department of Oral and Maxillofacial Surgery, School of Dentistry, Pusan National University, Yangsan, South Korea. 2. Department of Orthodontics, School of Dentistry, Pusan National University, Yangsan, South Korea. 3. Department of Tissue Engineering, Regea Institute for Regenerative Medicine, University of Tampere, Tampere, Finland; Department of Oral and Maxillofacial Surgery, University of Oulu, Oulu, Finland. 4. Department of Oral and Maxillofacial Surgery, School of Dentistry, Pusan National University, Yangsan, South Korea; Dental Research Institute, and Institute of Translational Dental Sciences, Pusan National University, Yangsan, South Korea. Electronic address: ydkimdds@pusan.ac.kr.
Abstract
PURPOSE: To investigate postoperative intersegmental displacement and relapse following bilateral sagittal split ramus osteotomy (BSSRO) by comparing three different fixation methods: group A (sliding plate), group B (miniplate) and group C (bicortical screws). MATERIALS AND METHODS: The present retrospective study included 55 patients with mandibular prognathism who were treated with BSSRO. To evaluate skeletal changes, cone-beam computed tomography was taken before surgery (T0), three days after surgery (T1), and 6 months after surgery (T2). Differences among the three groups were assessed using a one-way analysis of variance, where P < 0.05 was accepted as statistically significant. RESULTS: There were no significant differences among the three groups in demographic data and the amount of mandibular setback. In skeletal changes and condylar axis changes, there were no statistically significant differences among the three groups. However, there were statistically significant postoperative skeletal changes in group C (bicortical screws) at all landmarks. The mean horizontal relapse rate was 1.9% in group A (sliding plate); 4.8% in group B (miniplate); and 15.4% in group C (bicortical screws). CONCLUSION: The sliding plate system has good adaptability to the proximal segment after mandibular setback with BSSRO, and behaves according to semi-rigid fixation principles.
PURPOSE: To investigate postoperative intersegmental displacement and relapse following bilateral sagittal split ramus osteotomy (BSSRO) by comparing three different fixation methods: group A (sliding plate), group B (miniplate) and group C (bicortical screws). MATERIALS AND METHODS: The present retrospective study included 55 patients with mandibular prognathism who were treated with BSSRO. To evaluate skeletal changes, cone-beam computed tomography was taken before surgery (T0), three days after surgery (T1), and 6 months after surgery (T2). Differences among the three groups were assessed using a one-way analysis of variance, where P < 0.05 was accepted as statistically significant. RESULTS: There were no significant differences among the three groups in demographic data and the amount of mandibular setback. In skeletal changes and condylar axis changes, there were no statistically significant differences among the three groups. However, there were statistically significant postoperative skeletal changes in group C (bicortical screws) at all landmarks. The mean horizontal relapse rate was 1.9% in group A (sliding plate); 4.8% in group B (miniplate); and 15.4% in group C (bicortical screws). CONCLUSION: The sliding plate system has good adaptability to the proximal segment after mandibular setback with BSSRO, and behaves according to semi-rigid fixation principles.