In vitro biomechanical evaluation of modified plating techniques for bilateral sagittal split ramus osteotomy in...

The aim of this study was to compare the biomechanical properties of modified plate techniques using a newly designed three-dimensional test model after sagittal split ramus osteotomy. Fifteen synthetic polyurethane mandibular replicas were used and divided into 3 groups. Self-tapping 6-mm titanium screws with an outer diameter of 2.0 mm and private designed plates produced by 316-L stainless steel were used in the study. After the osteotomy, the distal part was advanced by 5 mm. The jaw models were placed to the three-dimensional test model designed by the authors, and the Instron Lloyd LRX device was used to apply a double-sided tensile force from the mandible angulus region of each group. Resistance forces that caused a displacement of 1.5 and 3 mm were recorded with the Instron program. The mean (SD) of the 3 groups were calculated using analysis of variance and the Tukey test. The results were compared statistically, with values of P < 0.05 determined as statistically significant. On the basis of the results of the Tukey comparison within the groups, there was a statistically significant difference between groups 1 and 2 and between groups 1 and 3 at both 1.5- and 3-mm displacement (P < 0.05). No significant difference was observed between groups 2 and 3 (P > 0.05). This test model was able to identify the most appropriate plate type of 3 different modified plate techniques after sagittal split ramus osteotomy.