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Bacteria and toothpasteFeatured science projectScience project video


Our hypothesis, that the amount of bacteria in the mouth will be reduced after brushing one's teeth with toothpaste, is proven to be true.

Toothpaste and proper brushing techniques are important for dental hygiene and keeping our teeth strong and healthy. Toothpaste is used not only for killing bacteria and preventing tooth decay, but also for teeth whitening and preventing bad breath.

Also consider

This science fair project may be repeated, this time, with swab sample from different locations in the mouth like the tongue.

Modify the science project experiment, using different brands of mouthwash.


How does toothpaste clean your teeth? -

Toothpaste -

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Time required:
1 hour to prepare, 4 days for science fair project
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The bacteria should be destroyed before being disposed of. Pour some bleach into the petri dish to kill all the bacteria before disposal.