Ex-vivo Smear Layer Removal Efficacy of Two Activated Irrigation Techniques After Reciprocating Instrumentation in Curved Canals
Tamara Costa Lopes Schiavotelo1, Marcelo Santos Coelho1, *, Luis Cardoso Rasquin2, Daniel Guimarães Pedro Rocha1, Carlos Eduardo Fontana1, 3, Carlos Eduardo da Silveira Bueno1
1 Department of Endodontics, School of Dentistry and Medicine, São Leopoldo Mandic University, Campinas, SP, Brazil
2 Department of Integrated Clinical Dentistry and Diagnostics, School of Dentistry, Federal University of Bahia, Salvador, BA, Brazil
3 Department of Endodontics, School of Dentistry and Medicine, Pontificia Universidade Católica de Campinas, Campinas, SP, Brazil
This study aimed to compare the effectiveness of two activated irrigation techniques in removing the smear layer after single-file reciprocating instrumentation in curved canals.
Materials and Methods:
Sixty distobuccal roots of maxillary molars were standardized to create a closed system, and then instrumented using WaveOne Primary (Dentsply Maillefer, Ballaigues, Switzerland) instruments. Fifty-four specimens were randomly distributed into 3 groups for final irrigation: Non-activated irrigation, passive ultrasonic irrigation (PUI), and EndoActivator (EA;Dentsply Maillefer, Tulsa, USA) irrigation. All specimens received 3 mL of 17% EDTA for 1 minute, followed by irrigation with 6 mL of 2.5% NaOCl. The apical, middle and cervical thirds of the specimens were analyzed using scanning electronic microscopy (SEM), and the amount of remaining smear layer on the canal walls was rated by three examiners using a five-category scoring system. Kendall’s concordance coefficient was used to assess inter-rater agreement. Kruskal-Wallis and Mann-Whitney (Bonferroni) tests were used to compare the scores.
Kendall’s concordance coefficient was ≥ 0.7, indicating an excellent level of agreement between the raters. No statistically significant difference in irrigation techniques efficacy for removal of the smear layer (p=0.061) was found for the apical third. The scores attributed to the specimens irrigated with the EA system were significantly lower than those of the other groups in the cervical and middle thirds (p< 0.05).
The efficacy of the EA system in removing the smear layer in the cervical and middle thirds of root canals instrumented with reciprocating motion was significantly higher than that of either PUI or non-activated irrigation. Both EA and PUI performed similarly in apical third.
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
* Address correspondence to this author at the Department of Endodontics, School of Dentistry and Medicine, São Leopoldo Mandic University, Campinas, SP, Brazil, Tel: +55 71 99168-1549; E-mail: firstname.lastname@example.org