The caries-preventive effect of xylitol/maltitol and erythritol/maltitol lozenges: results of a double-blinded, cluster-randomized clinical trial in an area of natural fluoridation.

Xylitol studies suggest caries reductions in the order of 50%. Based on animal/microbial studies, erythritol potentially has caries-preventive properties. However, clinical studies are required to confirm this. The aim of the study was to investigate the additional caries-preventive effect of xylitol/maltitol and erythritol/maltitol lozenges delivered at school, relative to controls receiving comprehensive prevention, in a low-caries prevalence population. A 4-year, cluster-randomized, double-blinded clinical trial. Five hundred and seventy-nine 10-year-old consenting subjects from 21 schools were randomly assigned to one of five groups. Four groups used the lozenges on school days, in three teacher-supervised sessions daily, over 1 or 2 years. The daily amount was 4.7 g/4.6 g for xylitol/maltitol and 4.5 g/4.2 g for erythritol/maltitol. The groups received free examinations and care in the public health centre. Four hundred and ninety-six children were analysed. The main outcome measure was dentin caries increment based on a clinical examination at 4 years since the start. The groups were compared in relation to the increment using hierarchical logistic regression to adjust for potential clustering. Use of xylitol/maltitol or erythritol/maltitol lozenges did not result in caries reduction. A strong relationship between baseline caries prevalence and the 4-year increment was observed (OR = 7.38; 95% CI: 3.78-14.41). The results suggest that in relatively low-caries conditions the school-based use of xylitol/maltitol or erythritol/maltitol lozenges would not have additional caries-preventive effect when compared with comprehensive prevention.