Are bicortical screw and plate osteosynthesis techniques equal in providing skeletal stability with the bilateral sagittal split osteotomy when used for mandibular advancement surgery? A systematic review and meta-analysis.

The objective of this study was to perform a systematic review and meta-analysis to test the null hypothesis that there is no difference in postoperative skeletal stability between bicortical screw and monocortical plate fixation after mandibular advancement surgery with bilateral sagittal split ramus osteotomy (BSSO). A comprehensive search of major databases (PubMed, EMBASE, and Cochrane CENTRAL) was conducted to locate all relevant articles published from inception to October 2015. Studies were selected based on inclusion criteria; randomized controlled trials, controlled clinical trials, and retrospective studies comparing bicortical screw vs. monocortical plate fixation after BSSO, reported in peer-reviewed publications in the English language, were considered eligible. Changes in linear measurements (horizontal and vertical) were analyzed. Five relevant studies were identified, involving 203 patients (bicortical screw n=98, monocortical plate n=105). No significant difference was found between monocortical plate and bicortical screw fixation in horizontal (P=0.099) or vertical measurement (P=0.882). Based on this review, there is overall agreement in the literature that the amount of advancement has a direct relationship with postoperative changes. The results of this meta-analysis support the hypothesis that there is no statistically significant difference in skeletal stability between bicortical screw and monocortical plate fixation of the BSSO following mandibular advancement surgery.