Abstract:
Introduction: The aim of this study was to determine the shaping abilities of three nickel-titanium (NiTi) endodontic file systems by comparing six parameters: canal deviation, apical foramen position, angle of curvature, radius of curvature, aberrations and instrumentation time. Methods: Thirty simulated S-shaped canal blocks were placed in a customized stand for imaging, and the glide paths were prepared using #10 K-files and #13, 16 and 19 PathFiles. The blocks were then randomly assigned into three groups (n=10): ProTaper Universal, ProTaper NEXT, and iRace. Each system was used per its manufacturer’s recommendation up to apical size #25. Pre- and post-operative images were superimposed and used to determine canal deviation at eight levels and any shifting in apical foramen position. Angle and radius of curvatures were measured both coronal and apical curvatures from pre- and post-operative images. The post-operative images were magnified to identify canal aberrations. Instrumentation times were recorded. Results: The iRace system resulted in the least canal deviation, while the ProTaper Universal system produced the most. All canal deviations were to the inner side of the curvatures. The apical foramen position was shifted to the outer side of the curvatures with marked differences among the groups. The ProTaper NEXT system produced the least canal aberrations and the ProTaper Universal system produced the most which was significant difference. There were no significant difference of changing of angle and radius of curvature among groups. There were significant difference of instrumentation time among three groups, iRace system required the least instrumentation time, while the ProTaper Universal system required the most. A 0.05 significance level was set for statistical analysis. Conclusion: The iRace system showed the least canal deviation at most canal levels, shifting in apical foramen position and instrumentation time while the ProTaper NEXT system produced the least canal aberrations. ProTaper Universal showed the most canal deviation at most canal level, shifting in apical foramen position and instrumentation time. Percent difference of angle and radius of curvatures were not significant difference among three groups.
