MICROHARDNESS OF HUMAN RADICULAR DENTIN AFTER CONDITIONING WITH DIFFERENT IRRIGANTS

S. Sunil Kumar, *Nagaswetha E., C. Sunil Kumar, Vamsee Krishna Nallagatla, K. S. Chandra Babu, R. Bharathi Suma

ABSTRACT

Introduction: Irrigating solutions used during root canal preparation to eliminate microorganisms can alter the chemical and physical properties of dentin, potentially increasing the risk of tooth fracture. Therefore, it is essential to select irrigants that offer maximum therapeutic benefits with minimal adverse effects. Methodology: Forty single-rooted maxillary central incisors were decoronated at the cementoenamel junction and sectioned longitudinally. Root segments were embedded in acrylic resin with the canal lumen exposed. Initial Vickers microhardness values were recorded, and samples were randomly assigned to four groups: Group 1 – Saline (control), Group 2 – 17% EDTA, Group 3 – Propolis, Group 4 – Bromelain. Each sample was treated with 2 ml of the respective irrigant for 5 minutes, rinsed with distilled water, and dried. Post-treatment microhardness was measured, and data were statistically analyzed. Results: All groups showed comparable baseline microhardness, highest in the propolis group (68.81 ± 4.36). Post-irrigation, all values decreased, with the greatest reduction in the propolis group (52.69 ± 4.69). Bromelain showed the least reduction, followed by EDTA and saline. ANOVA revealed significant differences in pre- and post-irrigation values (P < 0.05). Conclusion: All tested irrigants reduced root dentin microhardness in this in vitro study. Propolis caused the greatest reduction, while bromelain preserved microhardness closest to baseline. EDTA showed a moderate effect, similar to bromelain and saline. These results suggest bromelain may be a biocompatible alternative to traditional irrigants, preserving dentin integrity while potentially aiding smear layer removal.

Keywords: Microhardness, EDTA, Dentin, Propolis, Bromelain, Vickers micro-hardness tester.