The Comparison of Three Different Fixation Methods on Bilateral Sagittal Split Ra-mus Osteotomy Mandibular on a 3D of Fully Modelled Mandible by the Finite Ele-ment Method

Abstract

In this paper, a full mandibular CT-scan in a specific patient is used to model BSSO surgery. The purpose is to compare the three most common fixation methods which are used in BSSO surgery by finite element method. Three different fixations are studied in order to obtain the minimum displacement of the lower jaw and optimum stress and strain on the specified fixation. The methods are two parallel plates with four screws, the operation of triangular screw configuration and one plate with four screws. The plates and the screw are modeled precisely by point clouds of Synthes Brand’s plate and screw. The mechanical properties of the full mandibular and, to obtain a practical model after the surgery, the mean jaw forces are extracted from literatures. It is resulted that the minimum displacement and stresses on the mandible and fixation tools happened in the Triangular screw configuration model and the two other methods have higher stress and lower displacement. Therefore, the mandibular in triangular method, experiences little deformation and the screws tolerates lower stress and strain which is better than the other two methods.

Application of Finite Element Analysis in Oral and Maxillofacial Surgery—A Literature Review

“…The selection of appropriate bridging elements is also a key determinant of successful outcomes in all orthognathic surgeries. In bilateral sagittal split osteotomy (BSSO), FEA has been eagerly used to compare the stability of bridging the bony segments with various fixation systems [ 34 , 35 , 36 , 37 , 38 , 39 ]. For this purpose, Stróżyk et al created a three-dimensional digital isotropic model divided according to the BSSO line into three segments, with 5 mm gaps in between.…”

“…In this area, simplifications were also commonly adopted. The authors of much research on FEA assumed that distinguishing between cortical and cancellous bone was irrelevant and considered the investigated bone, in general, as homogenous, isotropic and linearly elastic material [ 12 , 35 , 38 ]. Another disputed issue is the fact that the conducted analyses varied in terms of the material constants used ( Table 5 ).…”

Three Different Fixation Modalities following Mandibular Setback Surgery with Sagittal Split Ramus Osteotomy: A Comparative Study using Three-dimensional Finite Elements Analysis

“…These methods differ in terms of the number, material, and angle of insertion, as well as the arrangement and layout of the fixation parts used. There are three types of intraoral fixation methods: rigid, semi-rigid/functional, and nonrigid 2 .The stabilization of bone pieces by intraoral fixation recuses the possibility of displacement owing to muscle strain. The advantages of this method include a faster recovery period and no need for mandibular (maxillomandibular) fixation 3 .…”

“…In vitro studies or finite element analysis (FEA) are used to assess the biomechanical stability of various fixation systems following mandibular osteotomy. The FEA is a numerical approach for solving differential equations in the fields of engineering, physics, and mathematical modeling 1 , 2 , 17 . The FEA-based research justifies its implementation in oral and maxillofacial surgery by providing advantages, such as precise analysis of stress distribution, analysis of complex mechanical systems and nonhomogeneous structures, as well as being less time-consuming and highly cost-effective 18 , 19 .…”

“…The FEA-based research justifies its implementation in oral and maxillofacial surgery by providing advantages, such as precise analysis of stress distribution, analysis of complex mechanical systems and nonhomogeneous structures, as well as being less time-consuming and highly cost-effective 18 , 19 . This method has recently become increasingly popular in the field of oral and maxillofacial surgery, especially in traumatology, zygomatic implantology, dental implantology, and orthognathic surgery 1 , 2 , 17 . This method assesses the biomechanical responses of the bone and also the biomechanical performance of different fixation methods under the applied load conditions 1 .…”