Abstract
Background The present study aimed to assess the efficacy of a heat-treated, FlexiCON nickel-titanium (Ni-Ti) rotary instrumentation system and compare it with existing commonly used instrumentation systems (hand file, ProTaper Universal, and WaveOne) using the EndoVac irrigation system. Methodology A total of 210 single-rooted, human permanent anterior teeth were equally divided into four groups of 50 teeth each (Group I for step-back, group II for ProTaper rotary, Group III for WaveOne reciprocating, and Group IV for FlexiCON rotary instrumentation system), and 10 teeth were used as controls. Canals were irrigated with EndoVac irrigation in each group. Extruded debris, irrigating solution, and Enterococcus faecalis were quantified and statistically analyzed. Results Group IV exhibited the least amount of debris, irrigating solution, and microorganisms than other groups, while Group I presented the most. FlexiCON with EndoVac irrigation demonstrated the least amount of microbe extrusion (14 colony-forming units (CFUs)) among the four instrumentation systems, whereas step-back instrumentation with EndoVac irrigation demonstrated the most (39 CFUs). The control group showed no debris, irrigating solution, or microorganisms. Conclusions FlexiCON Ni-Ti rotary instrumentation showed the least debris, irrigating solution, and bacterial extrusion compared with hand, ProTaper Universal, and WaveOne reciprocating instrumentation systems when EndoVac irrigation methods were used.