Abstract

Objectives: To evaluate the influence of the type of osteotomy in the inferir aspect of the mandible on the mechanical performance. Materials and Methods: The study was performed on 20 polyurethane hemimandibles. A sagittal split ramus osteotomy (SSRO) was designed in 10 hemimandibles (group 1) with a vertical osteotomy in the buccal side (second molar level) and finalosteotomy was performed horizontally on the lingual aspect, while the mandible body osteotomy was finalizedas a straight osteotomy in the basilar area, perpendicular to the body. For group 2, the same osteotomy technique was used, but an oblique osteotomy was done in the basilar aspect of the mandibular body, forming continuity with the sagittal cut in the basilar area. Using a surgical guide, osteosynthesis was performed with bicortical screws using an inverted L scheme. In both groups vertical compression tests were performed with a linear load of 1 mm/min on the central fossa of the firstmolar and tests were done with models made from photoelastic resin. Data were analyzed using Student’s t-test, establishing a statistical significance whenP<0.05. Results: A statistical difference was not observed in the maximum displacements obtained in the two osteotomies (P<0.05). In the extensiometric analysis, statistically significantdifferences were identifiedonly in the middle screw of the fixation.The photoelastic resin models showed force dis-sipation towards the inferior aspect of the mandible in both SSRO models. Conclusion: We found that osteotomy of the inferior aspect did not influencethe mechanical performance for osteosynthesis with an inverted L sys-tem.