Guys, let me see if I can give you an idea about fluoride. Yes, too high a dose can cause fluorosis- that's how the anti cavity effects were discovered. It was noted that people with fluorosis did not get cavities. Research showed the optimum level for cavity prevention that did not disfigure the teeth.
Ingestion is actually important, as the F is laid down in the developing teeth, making them decay resistant throughout life. Ingestion is important only in the years that the teeth are developing within the jaws.
If you are on well water, the ideal would be to have your water tested for F. If there is naturally occurring F, You can then determine the correct level of F supplementation to acheive the optimum level.
Topical fluorides are helpful but do not provide the benefits of systemic F during tooth development.
A completely sugar free diet would be beneficial but is hardly realistic. Egyptian mummies show significant amounts of tooth decay even though they had no sugar in their diet.
I hope this answers some of your questions. This is my opinion, of course.
Please be aware there is a lot of misinformation on the Internet.

How perfect is this for me? I am a dentist, and I know that fluoridation is the number one, most effective public health measure ever taken. Take fluoridation away, and cavities will increase by about 80%, and middle class Americans are less able to pay to fix their teeth than 50 years ago.
That's the practical side.
My philosophical side is aganist any government intervention and/or coercion, and I would be against fluoridation on that basis.
But arent' there about a million more important issues to address?