[Caries-statistical results after 15 years of fluoridation in Basle]

Fluoride (1 ppm) has been added to the drinking water in Basel, Switzerland, since May of 1962. The effects of this fluoridation on the teeth was studied at five year intervals in a total of 9042 school children between the ages of seven and fifteen. During the course of the control examinations, a statistically significant reduction in the frequency and experience of caries for all age groups was observed. Caries were reduced by 60% and more. The increase in the number of children with caries-free teeth in all age groups was statistically significant.