When did my Massachusetts community become fluoridated? What does fluoridated water do anyway?

Grand Rapids, Michigan was the first community in the United States to become fluoridated in 1945. Five years later, when the schoolchildren there exhibited significantly reduced tooth decay, the surrounding communities followed suit. However, fluoridating individual communities became a hotly contested political issue, and Massachusetts residents were wary – in 1967 only 8.2% of communities were fluoridated, almost last in the nation. Through political action and education by the dental and public health community, fluoridated water was slowly accepted in Massachusetts. By 2010, 61% of Massachusetts residents enjoyed fluoridated water – you can look up your community here:

fluoride-census Mass 2010

OK, but what does fluoridated water do, anyway? Fluoride in drinking water is highly effective if present while teeth are developing, from birth to age 8-10.  (Surprisingly, baby teeth are already developing at 6 weeks gestation, with calcified structure typically evident at 3-4 months. At birth, the enamel formation of most permanent teeth is already underway.)  Fluoride is incorporated into developing tooth enamel until age 10, and the resulting structure is highly decay resistant. 

Fluoride in toothpaste and drinking water is still effective after age 10 as a topical, i.e. surface contact agent, as its absorbed into tooth enamel to a small degree with consistent use. However, this only provides a fraction of the benefit of fluoridated water. 

Note that natural water only contains trace amounts of fluoride, and is not an effective systemic tooth decay preventative. Thus well water, often from artesian wells, and bottled water, which generally comes from natural springs, are not effective at tooth decay prevention.