Effect of different chelating agents on bovine tissue dissolving capacity of sodium hypochlorite

Abstract

Background: The success of endodontic therapy depends on thorough cleaning of the canal system. This is done by the use of various irrigants together with mechanical cleaning. The most popular irrigant used is sodium hypochlorite (NaOCl) in different concentrations. It has an added advantage in that it is a tissue dissolvent. To improve the removal of the smear layer in the canal, NaOCl is used with chelating agents such as ethylenediaminetetraacetic acid (EDTA), etidronic acid, or chitosan. The aim of this study was to evaluate the effect of different chelating agents when used with NaOCl on tissue dissolving capability. Materials and Methods: Cleaned bovine tissue was cut into equal pieces of 4 mm × 4 mm × 2 mm and divided into 60 samples having a weight of 70 ± 3 mg. Irrigant solutions were divided into four groups. Group 1: 3% NaOCl, Gp 2: 3%NaOCl + 17% EDTA, Group 3: 3% NaOCl + 18% Etidronic acid, and Group 4: 3% NaOCl + 0.2% chitosan in acetic acid. Samples were taken into test tubes and kept in 10 ml solution of each group for 10 min. Later, samples were taken out from solution and washed with distilled water, blotted dry, and weighed again for change of weight. The difference between the initial and final weights was used to calculate the weight loss. Results: There was a significant difference between the sample weight before and after treatment for all the groups. NaOCl (Group 1) showed best percentage difference of weight loss, followed by NaOCl + Etidronic acid (P < 0.05), then NaOCl + EDTA (P < 0.05) and least with NaOCl + Chitosan (P < 0.05). Conclusion: Etidronic acid has shown better dissolution capacity as compared to EDTA and chitosan group when used with NaOCl.

Keywords

• chitosan
• ethylenediaminetetraacetic acid
• etidronic acid
• sodium hypochlorite