This study was designed to evaluate the cutting efficiency of heat-treated endodontic file under two different torque setting 1.5 Ncm as a recommended torque and at a higher torque 4.5 Ncm. Material and method: 40 Race Evo sets of files were used to shape 400 acrylic resin canals with angle of curvature less than 30⁰ a length of 16 mm. Samples were divided into two groups depending on torque. Grou...