Effect of Xylitol Chewing Gum on Mutans Streptococci and Lactobacilli

Xylitol has been shown to be a successful dental caries preventive agent both in animals and humans. Objectives: to observe the effect of xylitol chewing gum on salivary mutans streptococci, salivary lactobacilli and plaque mutans streptococci, and to observe whether the effect is related to xylitol content in chewing gum. Methods: 892 9-year old students in 8 primary schools were assigned to 100% xylitol, 50% xylitol, and control groups based on school. Students in xylitol groups chewed gum four times one day during school time. After 2 years, 790 students were examined. The salivary and plaque MS, salivary LB levels were measured by Dentocult SM and Dentocult LB. Results: there was no statistical difference among 3 groups at baseline. After 2 years, the salivary and plaque MS, salivary LB levels were significantly lower in the xylitol groups than in control group, however the difference between 100% xylitol and 50% xylitol groups was not statistically significant. Conclusions: regular xylitol consumption was associated with a statistically significant reduction of oral mutans streptococci and lactobacilli levels.