Comparative evaluation of various chelating agents on the microhardness of root canal dentin: An in vivo study

Introduction: This study aims to compare and evaluate the effects of Irritrol and 17% ethylenediaminetetraacetic acid (EDTA) on the root dentin microhardness. Materials and Methods: A diamond disc was used to decoronate 15 human noncarious maxillary central incisors at the cemento-enamel junction. Thirty root segments were set in an acrylic block with the dentinal surface exposed. All root segments were irrigated with sodium hypochlorite solution before treating with test solutions. Microhardness (Vickers hardness number [VHN]) values of each specimen were determined using Vickers indenter before and after treatment with test solutions (Irritrol and EDTA). The mean lengths of the two diagonals formed due to indentation were used to compute the microhardness value. VHNs were determined using these measurements. Mean differences between (Irritrol and EDTA) and within the (before and after) group were compared using Student's t-test. Intragroup comparison was done using F-test (one-way ANOVA) at different areas of radicular dentin. α =0.05 was the set level of significance. Results: Both the test solutions showed a reduction in microhardness in coronal and middle third of root canal dentin, but the reduction in apical third (P < 0.05) was significantly more with respect to EDTA when compared to Irritrol. Conclusion: Irrigation using 17% EDTA and Irritrol decreased the root dentin microhardness; however, in the apical third, there was a less decrease in microhardness by Irritrol when compared to EDTA.