Finite element analysis of roots restored with metallic posts and ceramic crowns during occlusal movement

Oral rehabilitation of endodontically treated roots is inherently difficult, and the functional loads result in extremely complex structural responses of the oral tissues. The objective of this study was to evaluate, by finite element analysis, stresses induced in an endodontically treated maxillary central incisor that was restored with a cast metallic post and core system and a overlying ceramic crown during contacts with the antagonists. A 3D model of a central incisor was created: intact teeth, unrestored teeth with chamfer marginal preparation, the same tooth restored with a cast posta and core system and a full pressed ceramic overlying crown. The tooth preparation and the restorations were designed. Models were exported in Ansys finite element analysis software for structural simulations. Maximal equivalent stresses were recorded in the tooth structures and in the restorations for all contact areas. The values were higher in the crowns, and increase significant in the marginal segments of the contact areas. Regarding the stress distribution in the prepared teeth, the areas were larger around the marginal line. In the post and core system higher stress values were recorded oral. Key-Words: ceramic crown, post and core system, root, oclusal movement, finite element analysis, stresses.