| MadSci Network: Microbiology |
Fluoride doesn't work by killing the bacteria in your mouth. It actually reacts with the teeth and makes the outer surface (the enamel) stronger, so that it cannot be attacked by the acids produced by bacteria as easily. It also helps the body to "remineralize" small cavities -- in other words, it helps the body to fill in very small holes that formed in the teeth by bacteria.
To a certain extent, fluoride may also make it more difficult for the bacteria in your mouth to produce the acids that lead to tooth decay.
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