dude, here is the Canadian Dental Association's position on the use of fluoride:
http://www.cda-adc.ca/_files/position_statements/fluorides.pdf
Do you know how much more caries ppl will have if they drink non-fluoridated water? That can be a huge burden for those who don't have dental insurance. Dentists probably will earn more if there's no fluoride in drinking water.
The shade of teeth color is determined by many factors. Genetic, drugs you take (such as tetracyclin), what you eat (tea, coffee). Unless you swallow dental fluoride foam, whole tube of toothpaste, it shouldn't be the sole determining factor of the yellow/grey color of your teeth.
I must say it can be really easy to trick ppl to believe some "scientific" stuff. the dihydrogen monoxide hoax is an excellent example: http://en.wikipedia.org/wiki/Dihydrogen_monoxide_hoax
[ 本帖最後由 bbqfish 於 2008-5-24 12:13 編輯 ] |