Add Yahoo as a preferred source to see more of our stories on Google. How does purple toothpaste work? It uses color theory’s principle of complementary colors. Complementary colors are shades that ...

Thanks for your great questions, Amelia. I’m a dentist, so I know a bit about how toothpaste works and what we used before it was invented. Toothpaste makes your mouth smell fresh and feel clean. If ...

Here's a fun fact: Toothpaste works to clean your teeth through the use of slightly abrasive substances, among other things like fluoride. Those little abrasive chemicals work to dislodge gross stuff ...

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