Vol. 2, Issue 4, Part A (2016)

Abstract: The aim of the present study was to compare and evaluate the resistance of old and new generation One Shape single file systems that work with continuous rotation to cyclic fatigue under a dynamic model. Twenty pieces of old generation and 20 pieces of new generation One Shape (25.06) files were included in the study. The files were used at 400 rpm and a 400 g cm^-1 torque for OGOS and 400 rpm and a 200 g cm^-1 torque value for NGOS according to the manufacturer's instructions until fracture. Two files from each group were examined with a SEM device to determine the fracture type. NGOS had a significantly higher cyclic fatigue resistance compared with OGOS (P<0.001). Within the limitation of the present study, the new generation One Shape NiTi file has been found more resistant to cyclic fatigue than the old generation One Shape NiTi file.