Skeletal Relapse after Correction of Mandibular Prognathism by Bilateral Sagittal Split Ramus Osteotomy

Received: 28 August 2008 Accepted: 14 January 2009 Abstract: Objective: The aim of this study was to assess skeletal relapse in patients who underwent mandibular setback by bilateral sagittal split ramus osteotomy (BSSRO) and osteosynthesis wiring techniques. Materials and Methods: In this semi-experimental study, 10 patients (8 women, 2 men) with 3-8 millimeters overjet underwent mandibular setback with BSSRO, osteosynthesis wiring and inter maxillary fixation (IMF) techniques for 6-8 weeks. They were studied before (T0), immediately after (T1), and 6 months after surgery (T2) using clinical and cephalometric indices. Then, the maximum changes occurred in sagittal, rotational and vertical planes were evaluated in three time intervals (T1-T0), (T2-T0), and (T2-T1). Wilcoxon paired test was used as a statistical approach for data analysis. Results: The highest degree of relapse occurred in the sagittal plane in mandibular setback surgery with BSSRO and osteosynthesis wiring and IMF techniques. The degree of relapse was irrelevant of setback. In addition, no patient showed the amount of relapse warranting another surgery after six months. Conclusion: BSSRO surgery with osteosynthesis wiring and IMF provides acceptable stability in mandibular setback.