Restor Dent Endod.  2021 Feb;46(1):e11. 10.5395/rde.2021.46.e11.

Smear layer removal by passive ultrasonic irrigation and 2 new mechanical methods for activation of the chelating solution

• Machado R
• Silva Id
• Comparin D
• Mattos BAMd
• Alberton LR
• Neto UXdS

• KMID: 2548046
• DOI: http://doi.org/10.5395/rde.2021.46.e11

Abstract

Objectives
The aim of this study was to compare smear layer removal by conventional application (CA), passive ultrasonic irrigation (PUI), EasyClean (EC), and XP-Endo Finisher (XPF), using 17% ethylenediaminetetraacetic acid (EDTA) after chemomechanical preparation, as evaluated with scanning electron microscopy (SEM).
Materials and Methods
Forty-five single-rooted human mandibular premolars were selected for this study. After chemomechanical preparation, the teeth were randomly divided into 5 groups according to the protocol for smear layer removal, as follows: G1 (control): CA of distilled water; G2 (CA): CA of 17% EDTA; G3 (PUI): 17% EDTA activated by PUI; G4 (EC): 17% EDTA activated by EC; and G5 (XPF): 17% EDTA activated by XPF. SEM images (×1,000) were obtained from each root third and scored by 3 examiners. Data were evaluated using the Kruskal-Wallis and Dunn tests (p < 0.05).
Results
In the apical third, there were no statistically significant differences among the groups (p > 0.05). In the cervical and middle thirds, the experimental groups performed better than the control group (p < 0.05); however, G2 presented better results than G3, G4, and G5 (p < 0.05), which showed no differences among one another (p > 0.05).
Conclusions
No irrigation method was able to completely remove the smear layer, especially in the apical third. Using CA for the chelating solution performed better than any form of activation.

Keyword

Cleaning; Irrigation; Root canal

Figure

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  Figure 1 Scanning electron microscope images representative of the root canal walls according to groups and thirds.

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