Toothpaste and floride treatments you spit out. There is a special 'baby' toothpaste sold in the stores. I asked my dentist if I should brush my babies teeth with regular kids floride paste or use the special baby paste and he said we should use baby paste because babies do not spit out the toothpaste like older kids and adults. Well, guess what. I DON'T SPIT OUT MY WATER AFTER I DRINK IT, EITHER.
The level of floride in drinking water is FAR FAR FAR lower than what is put into toothpaste... apples and oranges.