Stress prediction in a central incisor with intra-radicular restorations

A 2D finite element analysis was applied to calculate shear and von Mises equivalent stresses developed, under masticatory loading, in an upper central incisor restored with cast gold post and carbon fiber reinforced epoxy resin post. Based on the predicted shear stress levels, it is concluded that the gold post model is more prone to shear failure along the post-dentin interface. Whereas shear stress concentration also occurs in both models at the core-crown interface, the stress level predicted there is higher for the carbon fiber post model which would be more susceptible to crown displacement. Finally, the prediction of von Mises equivalent stress indicates a non-uniform distribution, with the stress preferentially concentrated in the gold post along its interface with the tooth dentin. For the carbon fiber post restored model, on the other hand, the von Mises stresses are more uniformly distributed achieving its maximum level in the tooth dentin

Virtual analysis of stresses in human teeth restored with esthetic posts

The use of intra-radicular posts for rebuilding of damaged teeth is a normal practice in contemporary dentistry. However, dental roots restored with posts are subjected to the risk of failure under occlusal loads, particularly in cases of small dentin thickness. This study adopted the finite element analysis to compare the elastic stress distribution in simulated endodontically treated maxillary central incisor restored with two different esthetic posts, a ceramic post and a prefabricated fiber glass post. Under masticatory load, the shear stress and von Mises equivalent stress were determined for the different regions of the two models. The results demonstrated that stress concentrations occurred mainly in the cervical dentin in the prefabricated fiber glass post model. The ceramic post model presented stress concentration in a region limited to the proper post adjacent to its apical end, thus preserving the root dentin