不同内固定方式预防下颌角囊性病变病理性骨折的三维有限元分析  

Finite element analysis on different types of rigid internal fixation for preventing postoperative fractures in cystic lesions of the mandibular angle

作　　者：郑萍 吕俊 黄君杰 徐帅 张纲 ZHENG Ping;LYU Jun;HUANG Junjie;XU Shuai;ZHANG Gang(Department of Oral and Maxillofacial Surgery,Second Affliated Hospital,Army Medical University(Third Military Medical University),Chongqing,400037,China)

机构地区：[1]陆军军医大学(第三军医大学)第二附属医院口腔科,重庆400037

出　　处：《陆军军医大学学报》2023年第19期2092-2098,F0003,共8页Journal of Army Medical University

基　　金：陆军军医大学军事医学高新技术培育项目(CX2019JS108);陆军军医大学第二附属医院临床重大创新特色技术项目(2018JSLC0022)。

摘　　要：目的建立下颌角囊性病变病理性骨折的三维有限元模型,对比分析8种钛板内固定方式治疗后下颌骨的生物力学变化,探讨钛板固定方式预防大型下颌骨囊肿病理性骨折的可靠性。方法选取1名30岁正常成年男性下颌骨建立单侧下颌角区域的囊性病变模型,模拟咬合力加载造成病理性骨折,获取最大临界囊性病变尺寸大小,比较相同力学条件下不同钛板固定方式的下颌骨生物力学特点及变化情况。结果当下颌角囊性病变尺寸超过24 mm×30 mm×30 mm时存在病理性骨折的风险;上缘采用1 mm厚钛板加双侧3孔钛钉固定,下缘采用2 mm厚钛板加双侧4孔钛钉固定,下颌角囊性病变区域应力最低,未超过下颌骨最大屈服强度,未发生病理性骨折。结论下颌角大型囊性病变口外手术刮除后采用钛板固定术区上下缘可以降低病理性骨折发生。Objective To build a model of postoperative pathological fracture of the mandibular angular cystic lesions through 3D finite element analysis(FEA),to compare and analyze the biomechanical changes of the mandible after treatment with 8 types of titanium plates,and explore the reliability of titanium plate fixation in preventing pathological fracture of large mandibular cysts.Methods A 30-year-old healthy male was volunteered and the scans of cone beam computed tomography of his mandible were collected to establish a unilateral cystic lesion model of the mandibular angle region to mimic the pathological fracture caused by occlusal force loading.On the basis of the maximum critical cystic lesion size,the biomechanical characteristics and changes in the mandible with 8 different types of titanium plate fixation under the same mechanical conditions were compared.Results The risk of pathological fracture existed when the cystic lesion size in the mandibular angle exceeds 24 mm×30 mm×30 mm.The stress in the lesion area was the lowest when the upper edge was fixed with 1 mm thick titanium plate and bilateral 3 screws,and the lower edge was fixed with 2 mm thick titanium plate and bilateral 4 screws.At the same time the maximum yield strength of the mandible was not exceeded and no pathological fracture of the mandible occurred.Conclusion The incidence of pathological fracture can be reduced by using titanium plate fixation on the upper and lower margins of the mandibular angle after extraoral surgical curettage for large cystic lesions.

关 键 词：颌骨囊性病变 病理性骨折 坚强内固定 有限元分析 

分 类 号：R319[医药卫生—基础医学] R687.32R782.4