Comparative Evaluation of the Effect of Herbal Irrigants on the Push-out Bond Strength of Epoxy Resin Based Sealer to Root Dentin: An In-vitro Study

Abstract

Introduction: Favourable outcome of root canal treated teeth depends on the irrigants used. Sodium Hypochlorite (NaOCl) is one of the most commonly used irrigants in endodontic treatment. NaOCl has cytotoxic effects; limited ability to eliminate bacteria, along with jeopardizing of the bond strength between epoxy resin-based sealers and root dentin. Contemporary medicine orchestrates the use of biological medical extract from natural plants. Herbal alternatives are coveted as they are readily available, less expensive, have enhanced shelf life and low toxicity. Despite that, literature is sparse regarding the effect of herbal irrigants on Push-out Bond Strength (PBS) of sealer to root dentin. Aim: To compare and assess the effect of the PBS of epoxy resin based root canal sealer to root dentin following the use of two novel herbal irrigants,10% proanthocyanidins (PAs) and 2% Azadirachta indica (neem extract) with 3% NaOCl. Materials and Methods: This in-vitro study was conducted in the Department of Conservative and Endodontics at KLE VK Institute of Dental Sciences, Belagavi, Karnataka, India, between June 2019 and August 2019. The study was done on 30 extracted single rooted human mandibular premolar teeth, of which root canals were prepared using rotary instruments. The use of standard susceptibility tests {Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentration (MBC)} was done to determine appropriate concentration of the irrigant against E. faecalis. The teeth samples were randomly divided into 3 groups (n=10 each). Group 1 has teeth irrigated with 3% NaOCl (control group), Group 2 has teeth irrigated with 10% grape seed extract (10% proanthocyanidins) and Group 3 has teeth irrigated with 2% neem leaf extract (2% Azadirachta indica). Obturation of all the three groups were done with F3 gutta percha and AH Plus sealer followed by PBS testing using universal testing machine. One way Analysis of Variance (ANOVA) and Tukey’s Post-hoc tests were used for statistically analysing the data. The p-value <0.05 was considered as statistically significant. Results: Group 2 had significantly higher push-out bond strength as compared to Group 3 (p-value <0.001). However, there was no significant difference seen between Group 2 and Group 1 (p-value=0.207). Conclusion: It was concluded that the PBS of 10% proanthocyanidins was the highest, followed by 3% NaOCl and Azadirachta indica. However, biocompatibility and safety of these novel intracanal irrigants has to be assessed with the help of further clinical and in-vitro experiments to validate these findings.

Keywords

• azadirachta indica
• irrigation
• proanthocyanidins
• root canal
• sodium hypochlorite