Water fluoridation began after research in the 1930s found that children living in areas having naturally occurring fluoride in the water had significantly less tooth decay and subsequently less tooth loss as teenagers and young adults than those children drinking water not containing fluoride.
Since around 1945, hundreds of cities, towns and communities have fluoridated their water supply to the optimum level of 0.7mg/L (less than one part per million). This has resulted in a significant decrease in the number of children and teens with decayed teeth.
The positive benefit has been so profound that the National Institute of Health considers water fluoridation to be in the top ten public health initiatives of the 20th century.
Fluoride works in two different ways in our bodies. It’s most effective when ingested by young children before their permanent teeth erupt. The fluoride in their system, even in tiny amounts, changes the structure of tooth enamel as it forms making it stronger and more decay resistant. Since permanent teeth begin forming at birth and continue to form until about age 10, it’s important our kids get the benefit of fluoridated water through adolescence.
Second, having trace amount of fluoride in our systems as adults results in small amounts of it in our saliva, providing our teeth a bit of protection against decay.
An excessive amount of fluoride is not good for our teeth or bodies. When too much is ingested over periods of time as permanent teeth are forming, white spots called fluorosis can occur in the enamel. Teeth with fluorosis are usually very decay resistant, but the white spots do not make for an attractive smile.
This is why water fluoridation is strictly controlled to a tiny amount.
Children younger than two or three years old who cannot spit out toothpaste should NOT be given fluoridated toothpaste for brushing. If they routinely swallow the paste instead of spitting it out, they may get more fluoride in their system than is desired.
Once teeth have erupted (when permanent teeth come up through the gum), fluoridated water plays a much smaller role. After eruption a fluoride varnish is applied to the surface of the teeth, continuing the anti-cavity effect.
Toothpaste and topical fluoride use a much higher concentration to get the mineral into the surface of the enamel. Since decay is a slow process that removes mineral from teeth and makes them softer, daily doses of fluoride in toothpaste helps harden teeth by re-mineralizing them to make them harder.
We feel very strongly about fluoride and its benefits for teeth.
Adults who had the advantage of fluoridated water, fluoride treatments and toothpaste as children have fewer fillings, crowns or missing teeth than those who are older and weren’t exposed to fluoride. It’s common for us to see patients in their 20s and 30s who’ve never needed a filling! Their early exposure to fluoride will save them thousands in dental costs in their lifetime. Now that’s a success we are proud of!