In vitro evaluation of six different mouthwashes against six oral pathogens

1Lecturer of Microbiology, Faculty of Applied Medical science, October 6th University, Egypt A b s t r a c t Dental caries and throat infections are still considered as serious public health problems and inflict a costly burden to health care services around the world and especially in developing countries. In the present study six mouthwashes were evaluated against six oral microorganisms using turbidity measurements and the antimicrobial effect of each mouthwash was detected by the agar well diffusion method. Of the six mouthwashes tested mouthwash A, B and C emerged as the most effective antimicrobial mouthwashes. Mouthwash C showed the highest effect at the concentrations 50% and 75% by the agar well diffusion method, against four of the oral microorganisms tested. K. pneumonia was the mostly affected bacteria showing the highest IZD after treatment with mouthwash C. TEM showed the effect of mouthwash C on K. pneumoniae as disruption of bacterial cell membrane and destruction of all internal cell contents. A combination between the most three effective mouthwashes A, B and C was done to investigate their synergestic or antagonistic effects compared to mouthwash C alone. It was surprising that the effect of mouthwash C alone was higher than the other tested combinations.