Effects of xylitol-containing chewing gum on the oral microbiota

In this interventional study, a randomized controlled trial was used to evaluate the short-term effects of xylitol-containing chewing gum on the salivary microbiota. In total, 70 healthy adult men recruited from the Japan Ground Self Defense Force participated in the study during a 2-day training at Yamaguchi camp, Yamaguchi Prefecture, Japan. The men were randomly divided into two groups: one group chewed two pieces of xylitol-containing chewing gum 7 times/day for 2 days (n = 34) and the other did not (n = 36). Baseline and follow-up stimulated saliva samples were collected and the salivary microbial composition was assessed using the 16S rRNA gene next-generation sequencing analysis. The total salivary bacterial count was quantified using a quantitative real-time PCR system. No statistically significant difference was found between the two groups regarding any parameter analyzed in the baseline samples; however, the follow-up samples of the test group showed significantly lower total salivary bacterial count than those of the control group. Conversely, no significant difference was observed in the overall composition of the salivary microbiota between the baseline and follow-up samples of the two groups. These results indicate that xylitol-containing chewing gum inhibits the increase in total salivary bacteria over a short time during which the salivary microbial composition is not affected.