Comparative Evaluation of Pulp Dissolution and Smear Layer Removal Properties of Various Herbal Extracts: An in vitro Study

Abstract

Abstract Introduction: Root canal treatment involves eliminating microorganisms and necrotic tissue through biomechanical debridement and root canal filling to prevent reinfection. Disinfection is enhanced by removing the smear layer, composed of organic and inorganic debris, using irritants like sodium hypochlorite (NaOCl) for organic dissolution and ethylenediaminetetraacetic acid (EDTA) for chelation. Despite their efficacy, these agents have limitations, such as cytotoxicity and dentinal erosion. Research into biocompatible alternatives, including herbal extracts and essential oils, shows promise for safer and more effective root canal disinfection. Materials and Methods: Eighty extracted single-rooted premolars were studied for pulp dissolution and smear layer removal. Neem leaf (Group A), orange peel (Group B) and grape seed (Group C) extracts were tested against 3% NaOCl (Group D) for pulp dissolution and 17% EDTA (Group E) for smear layer removal. Pulp dissolution was assessed by weighing specimens before and after immersion in solutions, while smear layer removal was evaluated using scanning electron microscopy. Results were statistically analysed. Results: On statistical analysis, NaOCl showed significantly higher pulp dissolution compared to experimental herbal extract at all-time intervals, i.e. 30, 60 and 90 min. On intergroup comparison of smear layer removal scores, 17% EDTA produced significantly higher smear layer removal with a mean score of 0.4 compared to other herbal extracts. Conclusion: Herbal extracts exhibited no significant pulp dissolution at 30, 60 and 90 min compared to NaOCl. Similarly, none of the herbal extracts were comparable to 17% EDTA in smear layer removal efficacy. However, amongst herbal extracts, grape seed showed significantly better smear layer removal than Orange peel extract.