Compression of stress distribution in pull out and push out bond strength test set ups: A 3-D finite element stress analysis

0 0 1 220 1260 demomac1111@gmail.com 10 2 1478 14.0 96 800x600 Normal 0 false false false EN-US JA X-NONE Objectives: The purpose of this study was to compare the stress distribution in pull out and push out test set ups using finite element analysis, and to highlight some parameters that might have important influence on the results. Methods: Three dimensional finite element analysis was performed using SolidWorks® 2005 3D CAD software. Model configurations were based on published experimental pull out and push out test set ups; therefore, in the push out test set up three different thicknesses of root slices (1, 2 and 3 mm) were modeled. Vertical tensile and compressive loads were applied in pull out and push out set up, respectively. COSMOSWorks™ 2005 software was used to compute the local Von Mises stresses for each of the models at the interface area. Then the patterns of stress distribution in studied models were compared. Results: Stress distribution was non-uniform in pull out model and pronounced stress concentration was observed at cervical one-third of the root and cement layer. In 1mm push out model, stress was distributed uniformly but by increasing the thickness of the root segment, stress concentrated at the upper end of the interface that was near to the loading point. Significance: Highly non-uniform stress may develop at the adhesive interface when the pull-out test is performed on entire post or the push out test is performed on thick root segments. Therefore, 1 mm root segments were preferred to achieve true bond strength measurements.