One hundred ninety-five women with high salivary levels of Streptococcus mutans (the bacterium associated with dental caries) were randomly assigned to chew xylitol gum (n = 120), or to receive treatment with chlorhexidine varnish (n = 32) or fluoride (n = 36). The women started using xylitol chewing gum three months after the birth of a baby and continued it until the child was two old. The chewing gum contained 65% (w/w) xylitol; the average frequency of consumption was four times a day, providing a daily xylitol dose of 6 to 7 g. The children did not receive any prophylactic measures against caries before the age of 2 years. Compared with the other treatments, maternal use of xylitol gum significantly reduced S. mutans colonization in the children's teeth at two years of age. At five years of age, the prevalence of dental caries was 70% lower in the xylitol group than in the other two groups. In all groups, the presence of S. mutans colonization in children at the age of two years was significantly related to each child’s age at the first development of caries.

Comment: The results of this study indicate that maternal use of xylitol chewing gum during the first two years of their child’s life (starting at age three months) can reduce the incidence of dental caries in the children, presumably by preventing the transmission of S. mutans from mother to child. Other studies have shown that children old enough to chew gum can reduce the incidence of dental caries by 30-80%, if they chew xylitol gum regularly. The protective effect of xylitol appears to be more pronounced for teeth that erupt after gum chewing has started than for teeth that are already present.

Isokangas P, et al. Occurrence of dental decay in children after maternal consumption of xylitol chewing gum, a follow-up from 0 to 5 years of age. J Dent Res 2000;79:1885-1889.