How do you prevent severe dental fluorosis?
White staining could mean you had too much OR not enough fluoride. You have to ask a dental hygienist or dentist what the white spots mean on your next visit. No matter what it is once the white spots occur there is no cure/ no way to fix it. Whitening teeth will only make those spots bigger. There is nothing wrong with fluorosis except that it doesnt look good. Nothing bad will happen to your teeth. Fluorosis only happens to teeth before they come in (erupt). And by your age almost all of your adult have come in. So you probably only have 4 more adult teeth coming in so there is nothing you can do about it now.
