Effect of finishing instrumentation using NiTi hand files on volume, surface area and uninstrumented surfaces in C-shaped root canal systems

Author(s)

Amoroso-Silva, P. ; Alcalde, M. P. ; Hungaro Duarte, M. A. ; De-Deus, G. ; Ordinola-Zapata, R. ; Freire, L. G. ; Cavenago, B. C. ; De Moraes, I. G.

• Document type: Journal article
• Source: International Endodontic Journal; v. 50, n. 6, p. 604-611, JUN 2017.
• Web of Science Citations: 10

Abstract

AimTo assess the effect of 90 degrees-oscillatory instrumentation with hand files on several morphological parameters (volume, surface area and uninstrumented surface) in C-shaped root canals after instrumentation using a single-file reciprocation system (Reciproc; VDW, Munich, Germany) and a Self-Adjusting File System (SAF; ReDent Nova, Ra'anana, Israel). MethodologyTwenty mandibular second molars with C-shaped canals and C1 canal configurations were divided into two groups (n=10) and instrumented with Reciproc and SAF instruments. A size 30 NiTi hand K-file attached to a 90 degrees-oscillatory motion handpiece was used as final instrumentation in both groups. The specimens were scanned using micro-computed tomography after all procedures. Volume, surface area increase and uninstrumented root canal surface were analysed using CTAn software (Bruker-microCT, Kontich, Belgium). Also, the uninstrumented root canal surface was calculated for each canal third. All values were compared between groups using the Mann-Whitney test and within groups using the Wilcoxon's signed-rank test. ResultsInstrumentation with Reciproc significantly increased canal volume compared with instrumentation with SAF. Additionally, the canal volumes were significantly increased after 90 degrees-oscillatory instrumentation (between and within group comparison; (P<0.05)). Regarding the increase in surface area after all instrumentation protocols, statistical analysis only revealed significant differences in the within groups comparison (P<0.05). Reciproc and SAF instrumentation yielded an uninstrumented root canal surface of 28% and 34%, respectively, which was not significantly different (P>0.05). Final oscillatory instrumentation significantly reduced the uninstrumented root canal surface from 28% to 9% (Reciproc) and from 34% to 15% (SAF; P<0.05). The apical and middle thirds exhibited larger uninstrumented root canal surfaces after the first instrumentation that was significantly reduced after oscillatory instrumentation (P<0.05). ConclusionsThe Reciproc and SAF system were associated with similar morphological parameters after instrumentation of mandibular second molars with C-shaped canals except for a higher canal volume increase in the Reciproc group compared to the SAF. Furthermore, the final use of 90 degrees-oscillatory instrumentation using NiTi hand files significantly decreased the uninstrumented canal walls that remained after Reciproc and SAF instrumentation. (AU)

• FAPESP's process: 14/03009-1 - Evaluation of the internal anatomy, instrumentation and retreatment techniques, using new mechanized instrumentation systems on permanent mandibulary second molars with fused roots
• Grantee: Pablo Andrés Amoroso Silva
• Support Opportunities: Scholarships in Brazil - Doctorate