The Effect of Access Cavity Design on Fracture Strength of Endodontically Treated Maxillary Premolars: Traditional Versus Conservative Preparation An In Vitro Study

Background: The purpose of this study was to compare the fracture strengths of maxillary premolar teeth prepared using traditional endodontic cavity (TEC) and conservative endodontic cavity (CEC) methods.Methods: Twenty Two extracted permanent human maxillary premolars were selected and randomly divided into two groups (n = 11/group). Group 1 Traditional Endodontic Cavity (TEC). Teeth were prepared with pulp chamber de-roofing and straight line access. Group 2 Conservative Endodontic Cavity (CEC). Teeth were prepared with the aim of preserving a soffit and pericervical-dentine. After access cavity preparation, all teeth were endodontically treated and restored with direct composite. Samples were mounted in self-cured acrylic resin then loaded to fracture in a universal testing machine and fracture values were recorded in newtons. The data were analyzed with Shapiro-Wilk test and T-test. The significance level was set at p ≤0.05 within all tests.Results: The fracture strengths of the samples in the conservative endodontic cavity (CEC) group were significantly higher than the traditional endodontic cavity (TEC) group (p<0.001).Conclusions: CEC preparation increased the fracture strength of maxillary premolar teeth compared with TEC preparation.