Xylitol gum, plaque pH and mutans streptococci

Abstract

This was a randomised clinical trial (note that the initial screening used a cluster randomised in part design). A total of 176 children (7-9 years old) with high MS scores were randomised into equal groups. For 6 months the xylitol group chewed five times during the day, 11.6 grams of a mixed gum containing 36.6% xylitol and other polyols (34.5%). while the control group chewed an identical dose of a non xylitol gum sweetened with a mixture of different polyols (71.1%). At baseline, 3 months, 6 months and 9 months (3 months after chewing) children were assessed for both plaque acidogenicity (after sucrose challenge) and salivary MS. Statistically significant differences were found between both groups at 3, 6 and 9 months, in 'area under the curve' (AUC) graphs, with lower plaque pH values in the xylitol group at 3 and 6 months and decreasing difference at 9 months. There was no significant difference between the maximum pH fall in both groups, and only small differences in minimum pH values at 3 and 6 months. There was significantly lower MS level in the xylitol compared with the control group. In addition there was a significant relationship between changes in MS levels, and changes in AUC. This randomised clinical trial suggests that the use of high-dose xylitol chewing gum has beneficial effects on plaque pH and MS in children at high risk of caries.