Assessment of Fatigue Failure of Endodontic Instruments

This article discusses the features of fatigue fracture of dental instruments used in endodontics. Fatigue tests were carried out on machine endodontic files under axial rotation with a radius R = 0.5 mm and a bend length L = 5, 10 and 15 mm. Common to all types of studied instruments was the maximum number of cycles, which was achieved with the smallest bend angle of 22.5 ° and a bend length of L = 5 mm. The analysis showed that cyclic durability increases with decreasing length and bending angle of the endodontic instrument.