The Smear Layer Removal Efficiency of Different Concentrations of EDTA in primary teeth: A SEM Study

Abstract

Objectives: The present study aims to evaluate the effects of different concentrations of ethylenediamine tetraacetic acid (EDTA) on smear layer removal in primary teeth by using scanning electron microscopy (SEM). Materials and Methods: The present study was performed with 28 extracted upper primary incisors assigned into four main groups (n=7) as 5%, 10% and 17% EDTA, and 1% sodium hypochlorite (NaOCl). The root canal surfaces (coronal, middle and apical) were scanned by SEM and scores of smear layer removal were recorded and compared after the root canal irrigation procedures. The results were analyzed using Kruskal–Wallis, Friedman and Dunn tests. Results: In all the root portions, although EDTA groups removed the smear layer more effectively than NaOCl, a statistically significant difference was observed between 17% EDTA and 1% NaOCl only in middle third (p <0.05). Also, smear layer was removed more effectively in coronal than apical in most of the groups (10% EDTA, 17% EDTA and 1% NaOCl) (p <0.05). Erosive defects were mostly seen in 17% EDTA and less than 10% EDTA group. These findings were not detected in 5% EDTA and 1% NaOCl group. Conclusions: It is possible to recommend the use of 5% EDTA irrigation solution in root canal treatment of primary teeth due to its similar smear layer removal efficacy with NaOCl and high concentration EDTA groups, low erosive potential and low concentration for periapical safety.