Design of class III intermaxillary traction titanium plate for boneanchorage based on finite element analysis

Abstract

The purpose of this article is to investigate the effect of different bending angles and traction directions of the traction arm on the stability of the titanium plate for bone-anchored maxillary protraction (BAMP). The titanium plate models with different bending angles of the upper and lower jaws were modelled in three dimensions, where the bending angles were 90°, 120°, 135°, 150°, 180° and recorded as U1-U5 and L1-L5 respectively. Finite element analysis was performed on the titanium plates with different structural parameters to complete the structural design selection study of the titanium plates. The displacement limit was defined and different angular tensile forces were applied to record the equivalent stress and displacement of the titanium plates under each working condition. A total of 120 sets of orthogonal simulation tests were designed, which showed that the stress values at U2, U3 and U4 are smaller at traction angles of 135° (66.152 MPa), 155° (59.015 MPa) and 175° (55.589 MPa) respectively. The displacement is correspondingly smaller at tensile angles of 135° (0.0073 mm), 150° (0.0056 mm) and 160° (0.0058 mm). L2 has the smallest stress value (50.491 MPa) and displacement (0.0062 mm) at a tension angle of 120°. Therefore, it is recommended to design a titanium plate with a mandibular traction arm bending angle of 120° for BAMP, and the traction arm bending angle of the maxillary titanium plate can be flexibly designed according to the clinical traction direction.