Antimicrobial efficacy of Hibiscus Fuscus garcke aqueous and ethanol extracts on tooth root canal microorganisms

Objective: To determine the antimicrobial efficacy of Hibiscus fucus extracts against six root canal microorganisms. Design: In-vitro analytical study. Setting: Department of Medical Microbiology, University of Nairobi. Material and Methods: Hibiscus fuscus twigs were collected, dried and ground into coarse powder which was macerated in sterile distilled water and 80% ethanol. The aqueous filtrates were lipolyzed, while the ethanol filtrates were reduced, and oven dried into powder. Tenfold liquid microdilution of 50 mg/ml Hibiscus fuscus extracts against pure strains of Enterococcus faecalis, Streptococcus mutans, Staphylococcus aureus, Fusobacterium nucleatum, Lactobacillus acidophilus and Candida albicans were incubated for 24 and 48 hours. Sodium hypochlorite 5.25% and 2% Chlorhexidine gluconate were the controls. Outcome measures: Percentage growth inhibition measured by changes in growth of microorganism cultures exposed to Hibiscus fuscus extracts. One-way analysis of variance and Tukey’s HSD test were used to test for any differences. Results: Fifty mg/ml Hibiscus fuscus aqueous extracts attained 122.01% ± 22.89, at 95% CI [108.79, 135] and (105.73% ± 7.64, at 95% CI [101.32,110.14] growth inhibition against Enterococcus faecalis and Fusobacterium nucleatum for 24 hours incubation similar to those obtained with 5.25% Sodium hypochlorite, and 2% Chlorhexidine gluconate at p=0.899947 (Tukey’s HSD). Other bacteria tested and Candida albicans showed resistance Conclusion: Fifty mg/ml Hibiscus fuscus aqueous extract showed bactericidal efficacy against E. faecalis (ATCC® 29212 ™), and F. nucleatum (ATCC® 25586™) comparable to 5.25% Sodium hypochlorite and 2% Chlorhexidine gluconate. Investigation to test pure Hibiscus fuscus extracts as a potential source of root canal irrigant is needed.