in vitro comparison of antimicrobial activity of aqueous decoction of coriandrum sativum, and dentol drop with chlorhexidine on streptococcus mutans.

background and objectives: dental caries is still remained as a major health problem. this problem has created a new interest to search for new antimicrobial agents from various sources including medicinal plants. since limited data is available so far regarding the antibacterial effect of coriandrum sativum seed and dentol drop against streptococcus mutans, this study aims to assess this activity. materials and methods: this experimental study was conducted in shiraz university of medical sciences. in vitro comparison of antimicrobial activity of aqueous decoction of coriandrum sativum seed and dentol drop with chlorhexidine against streptococcus mutans was evaluated using disk diffusion and broth microdilution assays. positive and negative controls were considered. the data was statistically analyzed by applying kruskal-wallis and tukey post-hoc test to compare the groups using spss software (version 17). results: dentol drop showed a remarkable antibacterial activity, in comparison with chlorhexidine, against s. mutans in the disk diffusion (p value = 0.005), and broth microdilution assays (p value = 0.0001). based on the results of this study, coriandrum sativum seed did not posses any antibacterial property. conclusion: coriandrum sativum seed showed no anti- streptococcus mutans activity. dentol drop exhibited a remarkable antibacterial activity against s. mutans when tested in vitro. dentol drop can be further studied as a preventive measure for dental caries.