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Comparative Evaluation of Canal Centering Ability of Single-file Retreatment System vs Multiple-file Retreatment
Sangkeetha Gnanasekaran1, Arasappan Rajakumaran2, Rajeswari Kalaiselvam3
1Department of Conservative Dentistry and Endodontics, Sri Ramachandra Dental College and Hospital, Sri Ramachandra Institute of Higher Education and Research (SRIHER - DU), Chennai, Tamil Nadu, India, Orcid: https://orcid.org/0009-0005-9789-6679.
Aim:
This study aimed to compare the canal centering ability (CCA) of a single-file retreatment system and a multiple-file retreatment system, with and without the use of gutta-percha (GP) solvent.
Materials And Methods:
Twenty extracted human mandibular molars with a canal access angle (CAA) of 20-40° were selected and treated endodontically. Samples were equally distributed into two groups, group I (10): HyFlex Remover, group II (10): ProTaper Universal Retreatment File, with two subgroups of five samples each: With solvent, without solvent. Retreatments were performed according to the manufacturer's instructions. Cone-beam computed tomography (CBCT) was used to evaluate CCA in coronal, apical, and middle thirds. Data were analyzed using an independent Student's t-test (p < 0.05).
Results:
Group I, with p-values of 0.001 at 3 mm, 0.024 at 6 mm, and 0.041 at 9 mm, showed significantly better centering ability than group II at all levels when xylene was used. Without xylene, both groups performed similarly in the apical and middle thirds, but group I outperformed group II at the coronal third (p = 0.001).
Conclusion:
HyFlex Remover demonstrated superior CCA across all root canal levels, regardless of solvent use. However, xylene significantly improved the performance of the ProTaper system at the apical and coronal thirds.
Clinical Significance:
Endodontic retreatment poses challenges in maintaining canal anatomy while removing obturating materials. This study was necessary to evaluate the CCA of single- vs multiple-file retreatment systems, with and without solvent use. Findings showed HyFlex Remover maintained superior centering ability, minimized solvent dependence, and provided clinicians with a safer, more reliable option for retreatment. How to cite this article: Gnanasekaran S, Rajakumaran A, Kalaiselvam R, et al. Comparative Evaluation of Canal Centering Ability of Single-file Retreatment System vs Multiple-file Retreatment System, with and without Gutta-Percha Solvent: An In Vitro Study. J Contemp Dent Pract 2025;26(9):898-903.
