【作者】 张晓；

【导师】 莫三心；

【作者基本信息】 郑州大学 ， 口腔修复学， 2005， 硕士

【摘要】 随着牙体治疗的广泛开展,桩核技术已成为残根残冠保存修复的重要技术方法,己为临床大量应用。为了有效地恢复缺损牙体的形态和功能,桩核必须粘固在根管内才能保证修复体在行使功能时不松动、不脱落;同时应能有效的保护牙根不折裂,因此,常用水门汀将根管桩核粘固在根管内。常用的水门汀有:磷酸锌水门汀(ZOP)、玻璃离子水门汀(GIC)、树脂水门汀(RC)和树脂加强型玻璃离子水门汀(RMGIC),它们不仅能为根管桩核提供固位、把整个桩核冠系统有机地结合在一起,而且能把修复体所受的应力通过其本身传递到根管牙本质,再传递到牙齿支持组织上,因此,使用不同弹性模量的水门汀粘固根管桩可能会引起牙本质的应力改变。本实验将采用三维有限元法(3D-FEM)来分析根管桩粘固后,不同的粘固水门汀对牙本质应力的影响,为临床应用提供理论力学的实验依据。 目的 本实验用3D-FEM分析常用水门汀粘固根管桩后牙本质应力峰值及应力分布的变化,来探讨水门汀对牙本质应力的影响以及在防止牙根折裂方面的作用。 材料和方法 选择标准离体无龋右上颌中切牙,经树脂包埋、多层螺旋CT断层扫描、扫描图形数字化输入AutoCAD建立三维模型,同时在三维模型上模拟出与实际相似的根管桩核、水门汀层、牙槽骨、牙周膜、牙本质、金属烤更多还原

【Abstract】 The usage of post-core cemented in root canal is a conventional method to restore the decayed teeth. In order to have effective retention, we must use cements which can lute the post and form post-core system between root canal and post. We have four kinds of different cements, which are zinc phosphate cement(ZOP), glass ionomer cement(GIC), resin cement(RC), resin-modified glass ionomer cement(RMGIC) and have different elastic modulus .Objective: This study aimed at analyzing the effects of the different luting cements on the peak of the dentinal stress and dentinal stress distribution in order to evaluate their roles in fracture resistance of endodontically treated teeth.Materials and methods: In order to know how post luting cements influenced dentinal stress distribution and the peak of the dentinal stress, a standard human maxillary central incisor was chosen. The standard three-dimension finiteelement models of maxillary central incisor restored with porcelain fused to metal crown and pure SDA-Ⅱpost which cemented by 4 different luting cements were constructed by AutoCAD. Then the finite element method(3-D FEM) was used to analyze the effects of four different luting cements which have different modulus of elasticity on the stress distribution of the dentin and the peak of dentinal stress. Two forces were used.Results: All these cements could lower the the peak of the dentinal stress, the first one was zinc phosphate cement(ZOP).The descendent rate of it was 46.3%.A11 the cements have not evident effects on the dentinal stress distribution.Conclusion: Within the limitations of this study, the zinc phosophate cements showed better condition than the other cements in the dentinal stress distribution.更多还原