【作者】 许崇涛；

【导师】 孙庚林；

【作者基本信息】 天津医科大学 ， 口腔临床医学， 2007， 硕士

【摘要】 目的：建立生物相似性和力学相似性较高的颅上颌复合体三维有限元模型以及颅面骨骨折及其坚强内固定三维有限元模型，并进一步分析颅面骨在功能状态下以及坚强内固定时的应力分布，探讨颅面骨骨折可能的发生机制及坚强内固定的理论基础，为颅面骨骨折的诊断、治疗以及防护提供参考。方法：以正常咬合的健康青年男性为研究对象，用螺旋CT断层扫描技术获得数据，通过DICOM标准将CT数据转移到个人计算机中，结合MATLAB大型科学计算软件、ANSYS有限元软件等方法在计算机上建立颅上颌复合体三维有限元模型以及颅面骨骨折及其坚强内固定三维有限元模型，对功能状态下颅上颌复合体应力分布进行分析；模拟分析颧骨在外力撞击下应力分布，探讨颧骨骨折的可能发生机制；初步分析应用小型钛板及微型钛板进行颅面骨骨折坚强内固定时功能状态下骨折断层的应力，骨折段位移，评价固定方法的效果。结果：1、建立了包括皮质骨、松质骨及牙齿的颅上颌复合体三维有限元模型，共有节点170，840个，单元673，618个；并进一步建立了颅面骨骨折及其坚强内固定三维有限元模型，共有节点255，970个，单元1，022，820个，其中包括颧骨、颧弓骨折，上颌骨骨折，眼眶骨折的坚强内固定三维有限元模型；2、在正中咬合时，颅上颌复合体梨状孔侧缘尖牙支柱处Von-Mises应力为7.997MPa、颧牙槽嵴支柱处Von-Mises应力为22.185MPa、颧弓区Von-Mises应力为14.830 MPa，翼突处Von-Mises应力为32.959MPa。颅面骨骨折坚强内固定时，应力集中于接骨板，其中小型钛板最大Von-Mises应力为101.478 MPa，微型钛板最大Von-Mises应力为85.316MPa，骨折段最大位移为0.003245mm；3、颧骨在外力撞击作用下，颧颞缝处Von-Mises应力为26.760 MPa、颧蝶缝处Von-Mises应力为43.476MPa、颧颌缝处Von-Mises应力为11.490 MPa。结论：1、通过螺旋CT扫描及三维重建，应用MATLAB大型科学计算软件、ANSYS有限元软件建立的颅上颌复合体三维有限元模型以及颅面骨骨折及其坚强内固定三维有限元模型，具有较好的生物相似性和力学相似性，可用于各种工况的有限元分析，可作为今后深入研究的原始模型；2、功能状态下，颅上颌复合体梨状孔侧缘尖牙支柱、颧牙槽嵴支柱、颧弓区、翼突处为应力较为集中的区域；3、颅面骨骨折应用小型钛板和微型钛板进行内固定是安全并且有效的；4、颧骨在外力撞击作用下，颧颞缝、颧蝶缝、颧颌缝为应力较为集中的区域，容易发生骨折和移位。更多还原

【Abstract】 Object: The purpose of this study was to establish three-dimensionalfinite element model (3-D FEM) of cranial-maxillary complex and rigid internalfixation (RIF) for craniofacial fractures with better similarity, and research onstress distribution during working occlusion and RIF of craniofacial fractures.Then the stress distribution was evaluated so as to provided theoreticallydirection for the diagnosis, protection of craniofacial fractures and RIF design.Methods: A young male skull with normal occlusion was adopted forCT scanned transverse section. Then the standard of DICOM was used totransfer the CT dates to personal computer. The super scientific calculatesoftware (Matlab) and the finite element software (ANSYS) were used to takeand analyse the date to establish the 3-D FEM of cranial-maxillary complex andRIF for craniofacial fractures. The working occlusion of cranial-maxillarycomplex were modeled; The stress distribution of zygomatic bone by attackingwas analysed to find the cause of zygomatic bone fracture; The stressdistribution and the mobility of fracture segment in craniofacial fractures withminiplates and microplates fixation under working occlusion, so as to evaluatedthe effect of the fixation method.Result: 1. A 3-D FEM of cranial-maxillary complex including cirticalbone, cancellous bone and dentition was established, which consisted of 170,840nodes and 673,618 elements. Then, a 3-D FEM of RIF for craniofacial fracturesincluding zygomatic bone fractures, maxilla fractures and orbital fractures werealso established, which consisted of 255,970 nodes and 1,022,820 elements.2. When cranial-maxillary complex was under working occlusion, the Von-mises stress of the caninus brace was 7.997 MPa, the zygomaticoalveolarcrest brace was 22.185 MPa, the zygomatic arch was 14.830 MPa, the pterygoidprocess was 32.959 MPa. There were higher Von-mises stress at the plates forRIF of craniofacial fractures, the highest Von-mises stress in the miniplates was101.478 MPa, in the microplates was 85.316 MPa, the most displacement offracture segment was 0.003245mm;3. When the zygomatic bone was attacked by force, the Von-mises stress ofthe zygomatitemporal suture was 26.760 MPa, the zygomaticsphenoid suturewas 43.476 MPa, the zygomatic-maxillary suture was 11.490 MPa.Conclusion: 1. The above mentioned methods were proved to befeasible in the establishment of 3-D FEM of cranial-maxillary complex and RIFfor craniofacial fractures and could improve the biomechanical similarity ofFEM effectively. The 3-D FEM could analyse the regularity of stressdistribution of craniofacial fracture by using RIF.2. There were higher Von-mises stress at canius brace, zygomaticoalveolarcrest brace, zygomatic arch, pterygoid process in the working occlusion.3. The RIF with miniplate and microplate were safe and effective.4. There were higher Von-mises stress at zygomatitemporal suture,zygomaticsphenoid suture and zygomatic-maxillary suture When zygomaticbone was attacked by force.The above position of zygomatic were feasible tofracture and displacement.更多还原