Department of Endodontics, Faculty of Dentistry, Grande Rio University UNIGRANRIO, Rio de Janeiro, Brazil.
Department of Endodontics, Faculty of Dentistry, State University of Rio de Janeiro UERJ, Brazil.
Eur Endod J. 2020 Dec;5(3):231-235. doi: 10.14744/eej.2020.16878.
To evaluate cyclic fatigue and torsional resistance of Reciproc Blue R25 (VDW, Munich, Germany), WaveOne Gold Primary (Dentsply Maillefer, Ballaigues, Switzerland), ProDesign R (Easy Equipamentos Odontológicos, Belo Horizonte, Brazil), and X1 Blue File (MK Life, Porto Alegre, Brazil) nickel titanium (NiTi) martensite reciprocating instruments.
In each group, ten instruments were tested for cyclic fatigue resistance using a stainless-steel artificial canal (curvature angle of 80° and radius of 3 mm) and ten instruments for torsional failure according to ISO 3630-1 standard. The surface of the fractured instruments was examined under scanning electron microscopy (SEM) at ×250 magnification. The results were compared statistically with one-way ANOVA and post hoc Tukey tests and the alpha-type error was set at 5%.
X1 blue file and ProDesign Rinstruments showed highest time to fracture than Reciproc Blue and Wave One Gold (P<0.05). However, no differences were found between X1 Blue File and ProDesign R (P>0.05). In addition, Reciproc Blue demonstrated highest time to fracture than WaveOne Gold (P<0.05). The lowest torsional resistance (1.0±0.2 N.cm) and angle of rotation (412º±46) was observed in the ProDesign R group (P<0.05). SEM analyses of fractured surfaces showed a crack initiation area and overload fast fracture zone after cyclic fatigue test, and concentric abrasion marks with microvoids at the centre of rotation after torsional failure experiment.
Overall, X1 Blue File and ProDesign R showed higher cyclic fatigue resistance than Reciproc Blue and WaveOne Gold instruments, while ProDesign R had the lowest torsional resistance and angular rotation values to fracture. SEM analysis of all instruments demonstrated typical failures features in both cyclic fatigue and torsional failure tests.
评估 Reciproc Blue R25（VDW，慕尼黑，德国）、WaveOne Gold Primary（登士柏麦尔乐，巴莱格，瑞士）、ProDesign R（Easy Equipamentos Odontológicos，贝洛奥里藏特，巴西）和 X1 Blue File（MK Life，阿雷格里港，巴西）镍钛（NiTi）马氏体往复仪器的循环疲劳和抗扭强度。
在每组中，使用不锈钢人工根管（弯曲角度为 80°，半径为 3mm）测试十个器械的循环疲劳阻力，根据 ISO 3630-1 标准测试十个器械的抗扭失效。使用扫描电子显微镜（SEM）在 ×250 放大倍数下检查断裂器械的表面。使用单因素方差分析和事后 Tukey 检验对结果进行统计学比较，误差类型为 5%。
X1 Blue File 和 ProDesign R 仪器的断裂时间均长于 Reciproc Blue 和 WaveOne Gold（P<0.05）。然而，X1 Blue File 和 ProDesign R 之间没有差异（P>0.05）。此外，Reciproc Blue 的断裂时间长于 WaveOne Gold（P<0.05）。ProDesign R 组的抗扭强度（1.0±0.2N.cm）和旋转角度（412°±46）最低（P<0.05）。循环疲劳试验后，SEM 分析断裂表面显示出裂纹起始区和过载快速断裂区，扭转失效试验后，中心旋转处出现同心磨损痕迹和微空洞。
总体而言，X1 Blue File 和 ProDesign R 显示出比 Reciproc Blue 和 WaveOne Gold 更高的循环疲劳阻力，而 ProDesign R 的抗扭强度和断裂时的旋转角度值最低。所有仪器的 SEM 分析均显示出循环疲劳和扭转失效试验中典型的失效特征。
