Silva Kaline de Moura, Machado Leonardo Mendes Ribeiro, Leite Milena Gomes Melo, Noritomi Pedro Yoshito, de Jesus Giorge Pessoa, de Moura Andrezza Lauria
Department of Oral and Maxillofacial Surgery, Federal University of Amazonas, Manaus, Amazonas, Brazil.
Department of Mechanical Engineering, University of Campinas, Campinas, São Paulo, Brazil.
Oral Maxillofac Surg. 2025 Feb 27;29(1):59. doi: 10.1007/s10006-025-01357-z.
To evaluate and compare, using finite elements three-dimensional (3D) analysis, two techniques of stable internal fixation in 2 patterns of sagittal split ramus osteotomy (SSRO) and the repercussions of occlusal load distribution in the postoperative period.
A 3D finite element model of a hemimandible was created. The models were divided into 2 split patterns of SSRO advanced 5 mm forward, a split pattern (1) following the Epker osteotomy design and another split pattern (2) following Posnick osteotomy design, simulated by CAD (Computer Aided Engineering) Rhinoceros 3D. Two internal fixation techniques were simulated by HyperMesh: A- one titanium miniplate of the Arnett system (1 mm) for orthognathic surgery fixed with four monocortical screws; B- one titanium plate fixed with four monocortical screws and one bicortical screw. Resistance, stress and displacement were analyzed applying a 200 N vertical load to the occlusal surface region of the mandibular first molar and a 100 N to the incisal surface of the mandibular central incisor.
The results were presented through the von Mises stress analysis. A difference in the displacement of the models fixed with only one miniplate and four monocortical screws was observed. The models with split pattern (2) presented smaller displacements when compared to the split pattern (1). For metallic components, the split pattern (2) exhibits lower strain values, although it has no significant difference.
The fixation technique B proved to be more rigid and lower stress values both in the bone and in the plate, as well as lower deformation and displacements were shown in comparison to fixation technique A for all mandibular movements and forces.
采用有限元三维（3D）分析方法，评估和比较矢状劈开下颌支截骨术（SSRO）两种模式下的两种稳定内固定技术以及术后咬合负荷分布的影响。
创建半侧下颌骨的3D有限元模型。这些模型被分为两种SSRO劈开模式，向前推进5毫米，一种劈开模式（1）遵循Epker截骨术设计，另一种劈开模式（2）遵循Posnick截骨术设计，由计算机辅助工程（CAD）软件Rhinoceros 3D模拟。通过HyperMesh模拟两种内固定技术：A - 用于正颌手术的Arnett系统的一块1毫米钛小板，用四个单皮质螺钉固定；B - 一块钛板，用四个单皮质螺钉和一个双皮质螺钉固定。在下颌第一磨牙的咬合面区域施加200 N垂直载荷，在下颌中切牙的切缘表面施加100 N载荷，分析阻力、应力和位移。
结果通过冯·米塞斯应力分析呈现。观察到仅用一块小板和四个单皮质螺钉固定的模型在位移上存在差异。与劈开模式（1）相比，劈开模式（2）的模型位移较小。对于金属部件，劈开模式（2）的应变值较低，尽管没有显著差异。
与固定技术A相比，在所有下颌运动和力的情况下，固定技术B在骨和板中都表现出更高的刚性和更低的应力值，以及更低的变形和位移。
