Influence of the Brushing Motions on the Dynamic Cyclic Fatigue Resistance of the Reciproc Blue Instrument: In vitro Study

Introduction

This study aimed to evaluate the dynamic cyclic fatigue resistance of Reciproc Blue files subjected to brushing motion.

Methods

Twenty Reciproc Blue files (R25, VDW, Munich, Germany) were employed for chemical-mechanical preparation in root canals of 3D printed replicas of mandibular molars. The instruments were divided into two groups (n = 10): Group brushing motion, instrumentation with brushing motions; Group without brushing motion , instrumentation without brushing motions. Subsequently, the same instruments underwent cyclic fatigue testing using artificial canals consisting of a stainless-steel plate and an apical segment with a 45° curvature. Data regarding the time to fracture, number of cycles to fracture, and length of the fractured fragment were collected and subjected to statistical analysis using the t-test or Mann-Whitney test, with a significance level of 5%. Additionally, the fractured fragments were examined under a scanning electron microscope.

Results

No statistical differences were observed between the groups in terms of time to fracture (P < .05), number of cycles to fracture (P < .05) and length of the fractured fragment (P < .05).

Conclusion

The brushing motion did not affect the dynamic cyclic fatigue resistance of Reciproc Blue files.