Evaluation of The Antibacterial Activity of Nasturtium officinale (watercress) Essential Oil with Calcium Hydroxide against Enterococcus faecalis Isolated from Root Canal (In vitro study)

Background: The application of herbal extracts in dentistry is considered as an interesting alternative to synthetic antimicrobials due to their lower side effects and ease of availability and for the effort to overcome the increased resistance to the common antimicrobial agents. The aim of this study: to investigate the antibacterial activity of Nasturtium officinale (watercress) essential oil in combination with calcium hydroxide against Enterococcus faecalis as intracanal medicament. Materials and Methods: Enterococcus faecalis was isolated from patients with necrotic root canal or failed root canal treatment. The sensitivity of Enterococcus faecalis to different concentrations of Nasturtium officinale essential oil and compared with calcium hydroxide paste was determined by using agar well diffusion method. The agar plate method was used to determine the minimum bactericidal concentration (MBC) of the tested oil against the bacteria. The combination of Nasturtium officinale essential oil with calcium hydroxide was evaluated and compared to calcium hydroxide paste with iodoform by using agar well diffusion method. Results: The essential oil of Nasturtium officinale exhibited antibacterial activity against Enterococcus faecalis, this activity was found to be increased as the concentration of extract increased and the difference was highly significant (P <= 0.01) among all concentrations and calcium hydroxide paste. The tested combination revealed larger inhibition zones than the ones formed by each tested agent individually. Conclusion: The essential oil extract of Nasturtium officinale is active against Enterococcus faecalis suggesting its potential to be used as an intracanal medicament alone or in combination with calcium hydroxide.