Portland, Oregon, whose residents have long resisted fluoridating city drinking water, will finally be joining the twentieth century in tooth decay prevention. (Yes, fluoridated drinking water became an official policy of the U.S. Public Health Service in 1951.) Just yesterday, the City Council approved a plan to add fluoride to Portland’s water by March of 2014.

By any reasonable assessment, Portland residents will be benefit from water fluoridation — which the Centers for Disease Control and Prevention called one of the greatest public health triumphs of the twentieth century. As ACSH scientific advisor Dr. Chic Schissel points out, even taking into account the fluoride we already get from eating canned food, drinking soda, and brushing our teeth, fluoridated water reduces dental decay by 25 percent. Unfortunately, Portland hasn’t been taking advantage of this public health triumph — and its tooth decay rate is among the worst in the country.

As far as opposition to fluoridation goes, the only valid criticism has been that too much fluoride may cause fluorosis, a condition that can lead to tooth enamel mottling and discoloration. Yet given that the Portland City Council has decided to limit the water fluoride levels to the lowest of government recommended levels (0.7 ppm), it seems unlikely that residents have any reason for concern. Instead, based on some very sound evidence, they can look forward to fewer trips to the dentist.