Has the prevalence of tooth decay decreased since water fluoridation began?
Yes. Independent studies initiated in 1945 and 1946 followed four communities and assessed the value of water fluoridation. By 1960, tooth decay rates in these communities declined, on average, 56% more than in demographically similar communities whose water supplies were not fluoridated. More recent studies show that water fluoridation will reduce tooth decay in permanent teeth by approximately 18-40%. Although this reduction in decay is not as dramatic as it was in the 1950s and 1960s, it is significant when compared to tooth decay in non-fluoridated communities.
