Micro-hardness of root canal dentin using various irrigating solutions: An in vitro study

Evaluation of changes in dentin microhardness during root canal irrigation using eighty extracted mandibular premolars is of interest. After decoronation and halving, baseline microhardness was measured with a Vickers tester. The samples were divided into four groups: control (Normal Saline), 3% Sodium Hypochlorite, 17% EDTA, and 2% Chlorhexidine Gluconate, with each immersed in their respective irrigants for 15 minutes at 37ºC. Results showed decreased microhardness in all groups except the control, with 17% EDTA causing the most significant reduction. Notable differences were found between groups 2, 4, and 1, but not between 1 and 3. Consequently, 2% Chlorhexidine is considered a suitable irrigation solution as it did not negatively impact dentin microhardness.