Comparison of the Antibacterial Properties of Three Mouthwashes Containing Chlorhexidine Against Oral Microbial Plaques: An in vitro Study

BACKGROUND: The mouth provides an environment that allows the colonization and growth of a wide variety of microorganisms, especially bacteria. One of the most effective ways to reduce oral microorganisms is using mouthwashes. OBJECTIVES: The aim of this study was to investigate the antibacterial effects of chlorhexidine mouthwashes (manufacture by Livar, Behsa, Boht) on common oral microorganisms. MATERIALS AND METHODS: In this in vitro study, isolated colonies of four bacteria, including Streptococcus mutans, S. sanguinis, S. salivarius and Lactobacillus casei, were prepared for an antimicrobial mouth rinse test. The tube dilution method was used for determining the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). RESULTS: The MICs for Kin gingival, Behsa and Boht mouthwashes were 0.14, 0.48 and 1000 micrograms/mL using the tube method for S. mutans, respectively. The MBCs for the mentioned mouthwashes were 0.23, 1.9 and 2000 micrograms/mL for S. mutans, respectively. The MICs for Kin gingival, Behsa and Boht mouthwashes were 0.073, 0.48 and 250 micrograms/mL using the tube method for S. sanguinis, respectively. The MBCs for the mentioned mouthwashes were 0.14, 1.9 and 1000 micrograms/mL for S. sanguinis, respectively. CONCLUSIONS: The Kin Gingival chlorhexidine mouthwash has a greater effect than Behsa and Boht mouthwashes on oral microorganisms and is recommended to be used for plaque chemical inhibition.