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

The model was generated using synthetic skull scan data, and surface model was changed into solid model with Rapid form. Modified anterior segmental osteotomy (Park’s method) was made using CATIA (Dassalut System Inc, Paris, France) program, and then 4 different types of fixation methods were used. Anterior load of 100 N was applied on the palatal surface of two central incisors with ANSYS V12 (ANSYS Inc, Canonsburg, Pennsylvania, USA) FEA software.

As results, Type 1 (L pattern) had stress of 187.8 MPa at plate, 45.8 MPa at screw and 15.4 MPa at bone around the plate. Type 2 (I pattern) had stress of 186.6 MPa at plate, 75.7 MPa at screw and 13.8 MPa at bone around the plate. Type 3 (inverted-L pattern) had stress of 28.6 MPa at plate, 29.9 MPa at screw and 15.3 MPa at bone around the plate. Type 4 (straight-“α” pattern) had stress of 34.8 MPa at plate, 36.9 MPa at screw and 14.9 MPa at bone around the plate. The deflection of the plates was 0.014 mm, 0.022 mm, 0.017 mm and 0.018 mm respectively.

It was concluded that Type 3(inverted-L pattern) fixation method provided more stability than others.

Conflict of interest: None declared.