Aim and objectives: Antibacterial activity of five different extracts of Cinnamomum zeylanicum was estimated and compared with the conventional root canal irrigant sodium hypochlorite on planktonic cells as well as on a 6-week biofilm.
Materials and methods: An estimated 10 g of the five different herbal extracts, namely methanol, ethanol, isopropyl alcohol, acetone, and chloroform were weighed and mixed with 20 mL of inert solvent. Zone of inhibition was assessed by the agar well diffusion assay and MIC (minimum inhibitory concentration) by the broth dilution assay. A total of 90 teeth samples were inoculated with E. faecalis (ATCC 29212) and were incubated for 6 weeks. The samples were assigned into six different groups, namely Cinnamomum zeylanicumm ethanolic extract, Cinnamomum zeylanicum ethanolic extract, Cinnamomum zeylanicum isopropyl alcohol extract, Cinnamomum zeylanicum acetone extract, Cinnamomum zeylanicum chloroform extract, and NaOCl. Time required to inhibit 6-week biofilm of E. faecalis was assessed using time kill curve with a time interval of 5, 10, 15, and 20 minutes. Statistical analysis was done using the Kruskal–Wallis test.
Results: The methanol, ethanol, isopropyl alcohol, acetone, and chloroform showed a complete eradication of Enterococcus faecalis—both planktonic organism and the 6-week biofilm.
Conclusion: According to the study conducted, methanol, ethanol, isopropyl alcohol, acetone, and chloroform extracts of Cinnamomum zeylanicum were found to be effective antibacterial agents against E. faecalis—both planktonic cells and 6 weeks biofilm formed on dentin substrate.
Clinical significance: Since cinnamon extract has a good antimicrobial activity almost at par with NaOCl, it could be a promising alternative to conventional irrigants.