Accumulated Hard Tissue Debris and Root Canal Shaping Profiles Following Instrumentation with Gentlefile, One Curve, and Reciproc Blue

Chi Wai Chan; Virginia Rosy Romeo; Angeline Lee; Chengfei Zhang; Prasanna Neelakantan; Eugenio Pedullà

doi:10.1016/j.joen.2023.07.019

Accumulated Hard Tissue Debris and Root Canal Shaping Profiles Following Instrumentation with Gentlefile, One Curve, and Reciproc Blue

J Endod. 2023 Oct;49(10):1344-1351. doi: 10.1016/j.joen.2023.07.019. Epub 2023 Jul 28.

Authors

Chi Wai Chan¹, Virginia Rosy Romeo², Angeline Lee¹, Chengfei Zhang³, Prasanna Neelakantan⁴, Eugenio Pedullà²

Affiliations

¹ Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China.
² Department of General Surgery and Medical-Surgical Specialties, University of Catania, Catania, Italy.
³ Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China. Electronic address: zhangcf@hku.hk.
⁴ Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China; Department of Endodontics, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, CA. Electronic address: pneelakantan@pacific.edu.

PMID: 37516238
DOI: 10.1016/j.joen.2023.07.019

Abstract

Introduction: This laboratory study aimed to evaluate the accumulated hard tissue debris (AHTD) and shaping performance following root canal instrumentation with a novel stainless steel rotary system (Gentlefile; MedicNRG, Kibbutz Afikim, Israel) compared with two single-file nickel-titanium instruments of different kinematics through micro-computed tomography (micro-CT) analysis.

Methods: Thirty isthmus-containing mesial roots of human mandibular molars with a curvature of 15°-35° were scanned with micro-CT at an isotropic resolution of 12 μm and randomly assigned to three groups (n = 10) according to the instruments used for canal preparation: Gentlefile (GF; #23/.04), One Curve (OC; #25/.06; Micro-Mega, Besancon, France), and Reciproc Blue R25 (RB; #25/.08; VDW, Munich, Germany). The AHTD, unprepared canal surface area, volume changes, surface area changes, and transportation were evaluated by comparing preoperative and postoperative micro-CT images. In addition, the time required for canal preparation was recorded. Data were statistically analyzed using the one-way analysis of variance (ANOVA) test or the Kruskal-Wallis test at a significance level of 5%.

Results: No significant differences were observed in the percentage of AHTD or in the unprepared canal surface area between the three groups (P > .05). The RB group demonstrated a significantly greater percentage increase in volume and surface area than the GF group (P < .05). The GF and OC groups showed significantly less transportation at 3 mm from the apex than the RB group (P < .001). The OC group required significantly less time for instrumentation than the RB and GF groups (P < .05).

Conclusions: Instrumentation with GF (#23/.04), OC, and RB yielded similar levels of AHTD and unprepared surface area in isthmus-containing curved canals. GF achieved this with less dentin removal and apical transportation, at the expense of a longer preparation time.

Keywords: Microcomputed tomography; reciprocation; rotation; transportation.

MeSH terms

Dental Pulp Cavity* / diagnostic imaging
Dental Pulp Cavity* / surgery
Equipment Design
Humans
Molar / diagnostic imaging
Molar / surgery
Root Canal Preparation*
Tooth Root
X-Ray Microtomography