RESUMO
Objective: Evaluating the canal-centering and apical transportation ability of endodontic file systems working with different kinematics but of similar cross section. Materials and Methods: Sixty human maxillary first molar mesiobuccal (MB) roots were assigned to three experimental groups based on instrumentation techniques: Reciproc Blue (RB), Mtwo (M2), and OneShape (OS). Pre- and post-instrumentation micro-computed tomographic analysis was performed. Centering ability and apical transportation were analyzed at 3 mm, 6 mm, and 9 mm short of the apex. Statistical analysis was conducted using Mann-Whitney U test and Kruskal-Wallis test. Results: OS showed better canal-centering ability than RB and M2 at 3 mm, 6 mm, and 9 mm. No significant difference among the tested groups was observed during the assessment of apical transportation (P < 0.05). Conclusion: The systems evaluated safely prepared curved MB canals with minimal canal transportation. OS showed superior canal-centering ability compared to the other two groups.
