Comparison of Antimicrobial Effects of Two Medicinal Plants Eryngium Planum and Stachys Lavandulifolia on Oral Pathogens in Vitro Models

Introduction: Nowadays, caries and fungal diseases make up a large part of dental diseases. Due to this, researchers are trying to find substances with fewer side effects. Therefore, the present study was conducted on two plants, Eryngium planum and Stachys lavandulifolia, on oral pathogens (Streptococcus mutans and Candida albicans). Materials & Methods: Ethanol extract was prepared by the maceration method. The effectiveness of extracts and their combinations were investigated on Streptococcus mutans and Candida albicans in comparison to positive controls by three methods such as disc diffusion, well, and biofilm prevention methods. In order to compare the growth of bacteria, SPSS V.17 and an analysis of variance test were used at a level of significance less than 0.05. Results: The present study showed that the antimicrobial effects of two plants (E. planum and S. iavandulifolia) are not significant compared to the antibiotics such as ciprofloxacin, nystatin, and chlorhexidine (P > 0.05). On the other hand, there was no change in improving the effect of two plants by combining different ratios of extracts (P > 0.05). Among the studied treatments, the antimicrobial effect of ethanol extract of E. planum (100%) was greater than others (P<0.05). The results showed that all samples were in the range of weak biofilm formation. Conclusion: Two medicinal plants, E. planum and S. iavandulifolia, did not show significant inhibitory effects on the growth of Streptococcus mutans and Candida albicans. compared to commercial mouthwash chlorhexidine and antibiotics ciprofloxacin and nystatin.