Assessment of Fatigue Resistance in Heat-treated Nickel-titanium Rotary Instruments with Single Canal Curvatures: An In Vitro Evaluation.

AIM AND

BACKGROUND

In a controlled, simulated root canal environment, this study examined and contrasted the resistance to cyclic fatigue of three heat-treated nickel-titanium (NiTi) rotary file systems. The goal of this work was to find systems with greater fatigue endurance because cyclic fatigue is a primary mode of instrument failure in current endodontics.

MATERIALS AND

METHODS

A total of 30 NiTi rotary instruments-10 from Hero Gold, NeoEndo Flex, and T-Pro-were put to the test. The dimensions of all instruments were the same: Size 25, taper 0.04, and length 21 mm. A specially designed device simulated a 60° canal curvature (8 mm from the tip) was used. Time to fracture (TTF) was recorded while the instruments were run at the torque and speed recommended by the manufacturer until they failed. A conventional procedure was used to calculate cycles to fracture (NCF). Measurements of fragment lengths were made, and one-way ANOVA and post hoc analysis were used to evaluate the significance of the findings.

RESULTS

Hero Gold outperformed NeoEndo Flex and T-Pro regarding fatigue resistance, as evidenced by considerably higher TTF and NCF values (p < 0.05). There was no statistically significant difference in fragment lengths between groups, suggesting that instruments consistently failed in the same places.

CONCLUSION

Hero Gold rotary files displayed the best fatigue resistance, indicating enhanced performance and durability in root canal applications.

CLINICAL SIGNIFICANCE: Understanding the differences in fracture resistance aids clinicians in selecting the appropriate instrumentation system for curved canals. How to cite this article: Boreak N. Assessment of Fatigue Resistance in Heat-treated Nickel-titanium Rotary Instruments with Single Canal Curvatures: An In Vitro Evaluation. J Contemp Dent Pract 2025;26(11):1047-1049.