In vitro antimicrobial effects of green tea, microwaving, cold boiled water, and chlorhexidine on Streptococcus mutans and Candida albicans on silicone pacifiers

Abstract

This study aimed to compare the antimicrobial effects of green tea, microwaving, cold boiled water, and chlorhexidine (CHX) on Streptococcus mutans and Candida albicans on silicone pacifiers. In this in vitro experimental study, 60 equal-size samples of silicone pacifiers were cut, ultraviolet sterilized, and randomly divided into two groups (n = 30) for immersion in 0.5 McFarland standard suspension of S. mutans and C. albicans. The samples in each group were then randomly divided into five subgroups (n = 6) for disinfection with 0.12% CHX, cold boiled water, green tea, microwaving for 7 min, and distilled water. The sample suspensions were cultured on blood agar (for S. mutans) and Sabouraud dextrose agar (for C. albicans) and incubated. The number of colonies was counted after 24 and 48 h. Data were analyzed using the Kruskal-Wallis and Mann-Whitney tests (P < 0.05). At 24 and 48 h, the S. mutans colony count was the lowest in CHX and green tea subgroups followed by microwave, cold boiled water, and distilled water subgroups (P < 0.05). CHX and green tea can significantly decrease the S. mutans and C. albicans colony count on silicone pacifiers.