Effects of short-term xylitol gum chewing on the oral microbiome

The aim of this study was to determine the effects of short-term xylitol gum chewing on the salivary microbiota of children. The study was a randomised, controlled, double-blind trial. Healthy children used xylitol chewing gum (xylitol group, n = 35) or sorbitol chewing gum (control group, n = 38) for 5 weeks. The daily dose of xylitol/sorbitol was approximately 6 g/day. At baseline and at the end of the test period, unstimulated and paraffin-stimulated saliva were collected. The microbial composition of the saliva was assessed using human oral microbe identification microarray (HOMIM). Mutans streptococci (MS) were plate cultured. As judged by HOMIM results, no xylitol-induced changes in the salivary microbiota took place in the xylitol group. In the control group, Veillonella atypica showed a significant decrease (p = 0.0001). The xylitol gum chewing decreased viable counts of MS in both stimulated (p = 0.006) and unstimulated (p = 0.002) saliva, but similar effects were also seen in the control group. The use of xylitol gum decreased MS, in general, but did not change the salivary microbial composition. Short-term consumption of xylitol had no impact on the composition of the salivary microbiota, but resulted in a decrease in the levels of MS.