Objectives: The purpose of this study was to evaluate fixation methods and find out which is the best for postoperative stabilization of the mandibular osteotomy using three-dimensional finite element analysis of stress distribution on the plate, screw, lower central incisors and surrounding bone, and displacement of the lower incisors.

Methods: The model was generated using synthetic skull scan data, and surface model were changed into solid model with rapid form. Bilateral sagittal split ramus osteotomy was made using CATIA program, and 8 different types of fixation methods were made. Vertical load of 10 N was applied on the occlusal surface of first molar.

Results: In cases of bicortical screws, von-Mises stress at screws and screw-hole, and deflection of lower central incisor were least in type 2. In cases of plates, von-Mises stress was least in type 8, and deflection of the lower central incisor was minimum in type 6 and 7.

Conclusions: It was concluded that type 2 (inverted L pattern with 3 bicortical repositioning screws) and type 6 (5 mm below from superior border of the mandible with 4 monocortical screws) fixation method provides more stability than others.

Conflict of interest: None declared.