The evaluation of different factors on stres configurations at endodontically treated teeth using finite element analysis

Following the endodontic treatment, teeth become more brittle than the vital teeth. It was noted that there occur fractures in maxillar premolar teeth after endodontic treatment.The aim of this thesis study is to analyse the stress formed by oblique and vertical forces in tooth tissues after composite restoration of endodontically treated maxillar second premolar. Also, the effects of the different restorative approaches and different base materials on stress were analysed using three dimensional finite element stress analysis.In the present study, maxillar second premolar tooth model was obtained by a special software (Rhinoceros 4.0, USA). On the model; MOD cavity, endodontic access cavity and root canal obturation were modelled. On this main model, fifteen different restoration models were prepared. For base material; resin modified glass ionomer cement and flowable composite resin were used. For restoration, the models representing two cusp cappings, palatinal cusp capping, standard MOD restoration, use of fiber woven in occlusal part and palatinal cusp capping with fiber woven were prepared. Then, stress in tissues was analysed using the method.Consequently, it became clear that in all models, application of oblique forces causes more stress than vertical forces and the highest values form in models where flowable composite resin was used as base material while the lowest values were observed in those in which no base material was used. It was found additional applications like cusp capping have no effect on reducing the stress formation in the the restoration of endodontically treated maxillar second premolar.