Comparative evaluation of smear layer removal efficacy of three herbal irrigants in the apical third of the root canal: An in vitro scanning electron microscopic study

Abstract

Background: Smear layer removal from the apical third of the root canal is critical and the widely used chemical irrigants have been associated with detrimental effects. Hence, the study aimed to evaluate the smear layer removal efficacy of three herbal extracts used as endodontic irrigants in the apical third of the root canal. Materials and Methods: Forty-eight single-rooted premolars were divided into three experimental groups and a control group and were irrigated with Neem extract (Group 1), Orange peel extract (Group 2), Tulasi extract (Group 3), 5.25% sodium hypochlorite (Group 4) and their effect on smear layer removal was examined under the field-emission scanning electron microscope. Statistical Analysis: Kruskal–Wallis test followed by Mann–Whitney post-hoc analysis was done to compare the mean smear layer scores between the four groups in the apical third of the root sections. Results: The lowest mean remaining smear layer scores was shown by Neem extract (0.83), followed by sodium hypochlorite (1.08), orange peel extract (1.67), and the highest for Tulasi extract (2.42). On intergroup comparison, Neem extract showed statistically significant less smear layer scores in comparison to Orange peel extract (P = 0.006) and Tulasi (P = 0.001). Neem showed no statistically significant difference with sodium hypochlorite (P = 0.37). Conclusions: Neem extract can be considered as an efficient smear layer removal irrigant in the apical third of the root canal.