Simulation Research On Mechanical Behaviors Of Maxillary Incisor Restored With Post And Core Crown

Post-core crown was applied effectively and widely to restore configuration and function of the destructed tooth structure, most importantly to protect the residual tooth structure from fracture under excess stress distribute in the tooth structure.Finite element analysis method was utilized as one of the chief methods to study the mechanics characteristic of materials to solve many clinic problems these years.Geometric comparability of the model was important to finite element analysis, and in this study, an accurate model, including post-core crown restoration of the maxillary first incisor, periodontal ligament and alveolar born, was created by SCT image ware, UG software and marc software.On the assumption that the displacement of tooth root was rigidity, present studies rarely consider the influence of periodontal ligament and alveolar born. In this study, static analyses of the restoration were study, considering rigid support and elastic support of the tooth root. And draw a curve represent the relationship between young modulus of different post-core crown combination and peak main stress distributed in the residual tooth structure.Currently, a lot of researches supposed that tooth and peridentium was isotropic, homogenized, continuous elastic material. But tooth, periodontal ligament and alveolar bone was anisotropic, non-liner material, especially, Sharpey fibers and matrix of periodontal ligament behaved viscoelasticly.When we assume the boundary conditions, we usually take the load as static mode, however, the bite force of the tooth is dynamic actually and the members will produce an acceleration which can not be ignored. Properties of creep, relaxation, dissipation and damping for viscoelastic materials such as periodontal ligament and the tooth itself are still not so clear until recent times. This paper analyzes the properties of creep, model and transient of the modified structure while the periodontal ligament and the tooth itself are in viscoelastic constitutive equation. Further more, the effects of the consideration of viscoelastic support are also studied and these results provide reasonable theoretical references for recent analysis which only uses the linear elastic method.