Why is it most people have bad teeth even though we have all this access to dental care?

People get braces, get their teeth whitened, have flouride, toothpaste, electronic brushes, waterpiks, floss, etc., and yet a large portion of the population ends up with dentures and a mouth full of fillings. Does anyone else find this strange? The more we progress the worse our teeth get? Is it the food? What is it? There are indigenous people that eat sugar cane all day long and have no access to toothbrushes and a large portion of them have lovely teeth that last their entire lifetime? What is up with our teeth? I spend so much time taking care of them and i feel sometimes unsure about it because are we all inevitably headed for dentures and veneers and crowns? Am i the only one so obsessed with teeth????
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I live in SW Florida, and am on well water! there is no flouride in the well water like there is in city water. and without floride in the water your teeth go to ****! I never had a cavity my whole life, until I moved here at 18. since my move I have had 4 cavities. and still have 1. I brush twice a day, floss, and use mouthwash. But it doesnt help... I cant afford dentists down here. Back home I could get cavities fixed for 50 dollars, here it costs 200 dollars. and thats cheap for here. So I blame the water.
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