Diferentes cimentos e retentores intrarradiculares na distribuição de tensões frente à simulação de ensaio de tração universal de coroas unitárias: análise tridimensional por elementos finitos

Abstract

The aim of this study was to evaluate the different luting agents and posts on the stresses distribution according to universal tensile test simulation of crowns using finite element three dimensional analysis. A sound maxillary central incisor were scanned using a three dimensional contact scanner (Modela, Roland) and the *.stl files were exported to CAD Rhinoceros-3D software. It was obtained the three dimensional sound model, from this it was simplified the crown and constructed a tensile disk device on incisal. Moreover, 12 restored models were generated according to studied factors: fiberglass post (FGP), cast post and core (CPC), ceramic crown (CC), metal crown (MC), Rely X ARC (ARC), Rely X Unicem (Unicem) and zinc phosphate (ZP). The models were exported using *.step files, to finite element analysis software (ANSYS Workbench 14.0) to perform the mechanical properties insertion, meshing and boundary conditions appliance. An 800 N load was applied under of the disk device area, along the tooth axis. The results were analyzed via maximum principal stress. It was concluded that in CPC models, there was stress concentration in MC and CPC, whereas in models restored with CC, stress concentrated priority in the crown. Furthermore, according to all luting agent, there was higher tensile stress concentration in incisal interface between crown and core and cervical interface between crown and dentin root. ARC presented lower tensile stress concentration in these regions than Unicem and ZP. The tensile stress concentration in incisal interface between crown and core was higher for MC than CC, in models with CPC and ARC. There was similar stress distribution between models with FGP.