Background: Better understanding is needed about the debris-and-irrigant-extrusion potential of the instruments used for root canal preparation procedures, manufactured of different heat-treated alloys.
Objectives: The aim of the study was to evaluate the single-file nickel-titanium (NiTi) rotary system OneShape® and compare it with 2 different heat-treated instrumentation systems produced by the same manufacturer - a single-file C-wire system (One Curve®) and a multi-file T-wire system (2Shape®) - in terms of debris and irrigant extrusion.
Material and methods: The mesiobuccal root canals of 51 extracted mandibular molar teeth were selected for the study. The roots were applied to the test apparatus prepared with the Myers and Montgomery method. The roots were divided into 3 groups according to the instrumentation system: OneShape; One Curve; and 2Shape. The root canals were prepared according to the manufacturer's instructions. The analysis of variance (ANOVA) and the post hoc Tukey tests were used to evaluate the significance of the amount of the extruded debris and irrigant (p < 0.05).
Results: The One Curve group produced less debris extrusion than the 2Shape group (p < 0.05). There were no significant differences between the 2Shape and OneShape (p = 0.136), or the One Curve and OneShape groups (p = 0.159). The weight of the extruded irrigant was significantly lower for the One Curve group as compared to other systems (p < 0.05). The mean weight of the extruded irrigant did not differ significantly for the 2Shape and OneShape groups (p = 0.976).
Conclusions: The C-wire One Curve system was associated with less apical irrigant extrusion in comparison with the OneShape and 2Shape systems. The amount of debris extrusion produced by the One Curve system was similar to that produced by the OneShape system and lower than in the case of the 2Shape system.
Keywords: Nitinol; endodontics; root canal preparation.