Efficacy of Combined Use of Different Nickel-Titanium Files on Removing Root Canal Filling Materials

S. Yürüker, M. Görduysus, S. Küçükkaya, E. Uzunoğlu, C. Ilgın, O. Gülen, B. Tuncel, M.O. Görduysus

Journal of Endodontics 2016; 42(3):487-92


INTRODUCTION: The aim of this study was to estimate the remaining amount of residual filling materials in root canals after retreatment using ProTaper Universal Retreatment (PTUR) files (Dentsply Maillefer, Ballaigues, Switzerland) alone or with the additional use of the Self-Adjusting File (SAF; ReDent-Nova, Ra'anana, Israel), Reciproc (VDW, Munich, Germany), or Hedström-files (H-file; VDW, Antaeos, Munich, Germany) with volumetric estimation using the stereologic method via cone-beam computed tomographic images.

METHODS: Forty-eight mandibular premolars with single canals were used. The canals were instrumented with ProTaper rotary instruments up to F4 and filled with gutta-percha and AH26 sealer (Dentsply De Trey, Johnson City, TN). All the samples were placed into the silicone models. Samples were scanned with cone-beam computed tomographic imaging and assigned into 4 groups (n = 12) according to retreatment files: the PTUR system group, the PTUR system plus SAF group, the PTUR system plus Reciproc group, and the PTUR system plus H-file group. The specimens were rescanned after retreatment procedures, and the volume estimations of the remaining filling materials were performed using the stereologic method. Data were analyzed using Kruskal-Wallis and Dunn tests.

RESULTS: There was no significant difference among the groups regarding mean percentage volumes of the filling materials before retreatment procedures (P > .05). None of the retreatment procedures provided complete removal of the filling materials. The additional use of the SAF did not significantly improve the removal of filling materials when compared with the PTUR system alone (P > .05). However, the additional use of Reciproc or hand H-files significantly improved the removal of filling materials when compared with the PTUR system alone (P < .05).

CONCLUSIONS: The additional use of files with different motion kinetics improved the removal of root canal fillings; however, none of the systems completely removed the root canal filling material from the root canals.


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yuruker retreatment


Additional Info

  • ReDent Nova’s note:

    This research was very far from using the Self-Adjusting File according to the clinical protocol, that defines the need to use the SAF for 4 minutes, in short pecking motions to WL, with continuous irrigation, and in re-treatments it is also advised to use gutta percha softener (chloroform).

    Instead, in this research (quote) "use of the SAF file was performed until reaching the WL".  The SAF was inserted and immediately pulled out of the canal, without the use of any form of gutta percha softening or any irrigant, without any pecking motions and without operating the SAF according to protocol. Improvement of the retreatment results after such poor use would be surprising.

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  • View abstract on PubMed. PMID: 26778268