DOI: 10.36347/sjds.2016.v03i12.003

Pages: 323-327

Abstract: The present study aimed to evaluate the effect of interruption on the cyclic fatigue of One Shape rotary NiTi instruments. 10 One Shape 25.06, 10 One Shape Apical 1 30.06 and 10 One Shape Apical 2 37.06 were included to the study. The instruments were subjected to dynamic cyclic fatigue test in continuous and interrupted rotation. In Group 1 the instruments were operated in continuous rotation and in Group 2 the instruments were stopped for 1 s in every 10 seconds. The lengths of the fractured tips were also measured and fractured surfaces were examined under scanning electron microscope. Data were evaluated using one-way ANOVA and Tukey post-hoc tests in SPSS software with 5% significance level. The interrupted rotation reduced the cyclic fatigue resistance of One Shape 25.06 significantly (P < 0.05). No statistically significant reduction was observed in One Shape Apical 1 and 2 instruments (P > 0.05). Interruption of rotation should be noted as a decreasing factor for the cyclic fatigue resistance of One Shape 25.06 NiTi rotary instrument.