Antibacterial Efficacy of Nigella sativa, Cassia auriculata, and Sodium Hypochlorite against Enterococcus faecalis and Streptococcus mutans: An In Vitro Study

Original researchin low numbers in primary endodontic infections but is frequently found in persistent or secondary infection. 12Significantly more viable E. faecalis cells have been detected in biofilms when co-cultured with S. mutans. 13Thus, an alternative to commercial irrigants with similar efficacy but lower toxicity and better patient acceptance is being explored against these organisms.In a systematic review of ten clinical studies on approximately 450 patients, it was found that natural irrigants such as castor oil, IntroductIonEndodontic infections are polymicrobial, with biofilm-forming bacteria invading the complex root canal system, leading to apical periodontitis. 1 Biofilms, protected by an extracellular polymeric matrix, are resistant to antimicrobial agents up to 1,500 times more potent than planktonic bacteria. 2Chemomechanical preparation reduces bacterial load and disrupts biofilms, aided by irrigants.An ideal irrigant should be antimicrobial, biocompatible, chelating, less-viscosity, tissue-dissolving, substantive, low in surface tension, effective against biofilms, nondiscoloring, and should not affect dentin properties. 3No single irrigant possesses all ideal properties.Sodium hypochlorite (NaOCl), the gold standard, offers strong antimicrobial activity and tissue dissolution, 4 but is cytotoxic and can cause hemolysis, ulceration, 5 emphysema, nerve paresthesia, ecchymosis, and swelling if extruded. 6Chlorhexidine (CHX) has good antimicrobial properties, 7 but combining with NaOCl is contraindicated due to the formation of parachloroaniline, a potential carcinogen. 8EDTA is a biocompatible chelating agent effective in smear layer removal but has weak antimicrobial activity, reduces NaOCl efficacy, and forms a precipitate with CHX. 9 S. mutans is associated with both primary and secondary endodontic infection. 10,11In contrast, E. faecalis is typically present