In vitro antimicrobial activity and comparison of the herbal extracts and sodium hypochlorite against primary plaque colonizers

Abstract

ABSTRACT NaClO is not suitable as a root canal irrigant because of its cytotoxicity. Good biocompatibility irrigants are required to have antibacterial activity. Many herbal products like Bee glue, Noni juice and Azadirachta indica have such properties. This study aims to investigate the possible effects of propolis, MCJ and Neem on bacterial infections and cytotoxicity in primary plaque colonizers. Direct contact and agar diffusion tests evaluated the antibacterial activity of herbal products against Fusobacterium, Candida albicans and Prevotella. The CCK 8 test determined the influence of these herbal products on the proliferation of human apical papilla stem cells (hSCAPs) and human periodontal fibroblasts (hPDLFs). A migration assay test was performed in addition to quantitative real-time PCR which measured osteogenic differentiation in hSCAPs. All herbal extracts tested in this study exhibited antibacterial activity comparable to NaClO against bacterial infections, while the strongest bacteriostatic effect was shown in the herbal treated group. These extracts had much weaker effects on the proliferation and migration of hSCAPs and hPDLFs as calculated by the CCK-8 assay against NaClO. Bee glue treatment had the most potent effect on osteogenic differentiation, followed by treatment with Noni juice and Azadirachta indica (Neem), while NaClO showed the lowest effect. For primary plaque colonizers of immature or advanced permanent teeth, Bee glue, Noni juice, and Azadirachta indica can be promising irrigants with good biocompatibility. Direct contact process and agar diffusion studies have tested the antibacterial activity against Fusobacterium, Candida albicans and Prevotella. The CCK 8 test determined the influence of these three plants on the proliferation of human apical papilla stem cells (hSCAPs) and human periodontal fibroblasts (hPDLFs). In order to examine migration ability, migration assay test was performed. Alizarin red staining, alkaline phosphatase (ALP) staining and quantitative real-time PCR measured osteo-/odontogenic differentiation in hSCAPs. All herbal extracts tested in this study exhibited antibacterial activity comparable to NaClO against bacterial infections, while the strongest bacteriostatic effect was shown in the treated group. These extracts had much weaker effects on the proliferation and migration of hSCAPs and hPDLFs as calculated by the CCK-8 assay against NaClO. Bee glue treatment had the most potent effect on osteo-odontogenic differentiation, followed by treatment with Noni juice and Azadirachta indica (Neem), while NaClO showed the lowest effect. For primary plaque colonizers of immature or advanced permanent teeth, Bee glue, Noni juice and Azadirachta indica (Neem) can be promising irrigants.