Comment by bobbylarrybobby

While tooth whiteness in the US is often divorced from tooth health, fluoride does add a yellowish tint to your teeth, so the healthiest teeth — those imbued with fluoride — are slightly yellow. (In fact when they first decided to add fluoride to water, one of the questions was just how much they could add before your teeth would turn completely yellow. Health-wise the yellowing was fine, but it was obviously visually unappealing.) Ugly teeth may be due to poor/lack of orthodontia, but it's probably not due to better dental care.