|MadSci Network: Microbiology|
Neat question! There is a previously posted question on the MAD Scientist network that is relevant to yours. Click here to see that answer as a preface to the answer of your question.
Mineral oxides are common ant-imicrobial ingredients found in toothpaste. However the main purpose of brushing your teeth is to remove food particles and thereby limit the amount of bacterial growth occuring in your mouth. Microbes are a normal part of our body's microflora so you will always have bacteria in your mouth.
The anti-bacterial agents in toothpaste are broad spectrum (meaning they can act on a broad variety of bacteria) therefore these compounds would have an effect on bacteria that are not normally found in the mouth.
Hope this helps
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