RESUMO
CONTEXT: Evaluation of microhardness of root dentin provides indirect information on the change in mineral content of root dentin thereby providing useful information on the bonding quality of resin-based root canal sealers. AIM: This study evaluated the effect of 17% EDTA, MTAD, and 18% HEBP solutions on the microhardness of human root canal dentin using the Vickers microhardness test. MATERIALS AND METHODS: Forty human single-rooted teeth were decoronated at the cementoenamel junction and sectioned longitudinally into buccal and lingual segments. Eighty specimens were divided into four groups (n=20). Group I was treated with distilled water (control), groups II, III, and IV were treated with 1.3% NaOCl as a working solution for 20 minutes followed by 17% EDTA, MTAD, and 18% HEBP respectively. The surface hardness of the root dentin was determined in each specimen with a Vicker's hardness tester. The values were statistically analyzed using the one-way ANOVA and post hoc Tukey multiple comparison tests. RESULTS: There was a statistical significant difference among all the groups (one-way ANOVA; P<0.001). Among the experimental groups, HEBP showed the highest dentin microhardness (53.74 MPa, P<0.001). Least microhardness was found with MTAD (42.85 MPa, P<0.001). CONCLUSIONS: HEBP as a final rinse appears to be a promising irrigation protocol with less impact on the mineral content of root dentin.