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. 2025 Apr;18(4):394-398.
doi: 10.5005/jp-journals-10005-3080. Epub 2025 May 19.

Comparison of Incidence of Instruments Separation among Endodontic Files Used in Reciprocation and Continuous Rotary Motion

Roohan M Sandhu  1 , Aashish Handa  1 , Kanwalpreet K Bhullar  1 , Tarunpreet K Dhami  1 , Gurleen K Oberoi  1 , Sukhman S Sran  2
Affiliations

Comparison of Incidence of Instruments Separation among Endodontic Files Used in Reciprocation and Continuous Rotary Motion

Roohan M Sandhu et al. Int J Clin Pediatr Dent. 2025 Apr.

Abstract

Introduction: The aim of root canal therapy is to shape and disinfect the root canal space to eradicate microbial pathogens using various endodontic files. However, instrument separation is an unfortunate sequela of endodontic instrumentation that can affect the outcome of endodontic therapy.

Aim: The current study aims to assess the incidence of instrument separation of three different file systems used in different operating motions (hand files, continuous rotary, and reciprocating files).

Materials and methods: In this study, three different file systems (n = 10 each)-Reciprocation File Neoendo (Orikam Healthcare India Private Limited, Haryana), Hand K-files (Dentsply Maillefer, USA), and HyFlex CM File (Coltene Whaledent, Altstetten, Switzerland)-were first used in vivo for biomechanical preparation of only mesiobuccal (MB) canals in molars. The same instruments were then transferred in vitro and used for root canal preparation of MB canals in extracted molar teeth. The number of canals shaped prior to instrument fracture was documented to calculate the incidence of instrument separation. The data was analyzed using one-way analysis of variance and post hoc Bonferroni analysis of variance.

Results: The results displayed that the Reciprocation File Neoendo had the lowest incidence of file separation at 10.5%, followed by Hand K-files at 18% and HyFlex CM files at 25%.

Conclusion: Reciprocation File Neoendo showed the lowest cyclic fatigue among all the tested groups, thus proving its superiority over the other file systems in terms of cyclic fatigue resistance. The current study also included the influence of intraoral conditions and root canal curvatures, as it was first used in patients after obtaining necessary informed consent.

How to cite this article: Sandhu RM, Handa A, Bhullar KK, et al. Comparison of Incidence of Instruments Separation among Endodontic Files Used in Reciprocation and Continuous Rotary Motion. Int J Clin Pediatr Dent 2025;18(4):394-398.

Keywords: Continuous rotary motion; Cyclic fatigue resistance; Hand K-file; Instrument separation; Reciprocation.

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Conflict of interest statement

Source of support: Nil Conflict of interest: NoneConflict of interest: None

Figures

Fig. 1:
Fig. 1:
Consolidated Standards of Reporting Trials diagram
Fig. 2:
Fig. 2:
PRILE flowchart
See this image and copyright information in PMC

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