A randomized, double blind clinical trial of the caries inhibition effects of dentifrices containing respectively monofluorophosphate and amine fluoride was performed. A third control group used a toothpaste without fluoride. A total number of 2008 schoolchildren ranging in age from 6 to 8 years and living in Strasbourg (France) participated in this study. After a baseline examination three groups were constructed with the block randomization technic. The caries inhibition effects of the three dental pastes were compared after 3 years of unsupervised use. The monofluorophosphate dentifrice showed a reduction of 7.02% for DMFT, 5.17% for DMFS and 25.26% for the df rate. The reduction of amine fluoride dentifrice caries was respectively 21.62% for DMFT, 20.94% for DMFS and 48.66% for the df rate.