Estimation of MBC: MIC Ratio of Herbal Extracts against Common Endodontic Pathogens.

Herbal extracts have evoked interest owing to the small number of terpenoids and phenolic compounds, which impart antimicrobial, antioxidant, and anti-inflammatory properties. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) of four herbal extracts (lemon grass oil, basil oil, peppermint oil, and Obicure tea extract) against endodontic pathogens along with the MIC: MBC/MFC ratio were evaluated. The antimicrobial activity by detecting the MIC of three essential oils and tea extract was evaluated against eight common endodontic pathogens by the broth dilution method, while MBC was detected by subculturing onto blood agar from the first -three to five tubes from the MIC dilution tubes (showing no turbidity), which were plated on blood agar.