Korean Journal of Health Promotion

: J Korean Dent Assoc. 2019;57(11):672-678. Published online November 30, 2019.
DOI: https://doi.org/10.22974/jkda.2019.57.11.004; 니켈티타늄 전동 파일의 기계적 특성 비교: Aurum Blue vs. Aurum Pro; 곽상원¹, 하정홍², 안상미³, 김현철⁴; ¹부산대학교 치의학전문대학원 치과보존학교실
²경북대학교 치과대학 치과보존학교실
³부산대학교 치의학전문대학원 치과보존학교실
⁴부산대학교 치의학전문대학원 치과보존학교실; Comparison of mechanical properties of nickel-titanium rotary files: Aurum Blue vs. Aurum Pro; Sang Won Kwak¹, Jung-Hong Ha², Sang Mi Ahn³, Hyeon-Cheol Kim⁴; ¹Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Pusan National University
²Department of Conservative Dentistry, School of Dentistry, Kyungpook National University
³Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Pusan National University
⁴Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Pusan National University

Abstract: AIM
The purpose of this study was to evaluate and compare the torsional fracture resistances, cyclic fatigue resistance, and bending stiffness of two nickel-titanium (NiTi) rotary instruments made of different heat-treated alloy: Aurum Blue (heat-treated) and Aurum Pro (conventional). Methods: Forty-five Aurum Blue and Aurum Pro NiTi files were selected for the three mechanical tests (n=15). For the torsional resistance test, 3 mm file tip was fixed and the shaft was driven clockwise at 2 rpm until fracture occurred by using a customized device. Cyclic fatigue resistance was evaluated by rotating instruments in artificial canal with dynamic mode. Bending stiffness was tested by observation of the bending moment on attaining a 45° bend. The results were analyzed by student-t tests at a significance level of 95%. The fractured surface of each groups were examined under a scanning electron microscope (SEM). Results: Aurum Blue showed significantly higher toughness, ultimate strength, distortion angle, and number of cycles to failure than those of Aurum Pro (p < 0.05). However, Aurum Blue and Aurum Pro did not differ significantly in terms of bending stiffness. SEM showed typical topographic appearances of the cyclic fatigue and torsional fracture. Conclusions: Under the limitations of this study, heat-treated instruments showed higher flexibility and fracture resistances than conventional NiTi instruments.

Keywords :Endodontic treatment;Nickel-titanium file;Torsional resistance;Cyclic fatigue resistance;Bending stiffness;CM-wire;