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Why Do We Need To Brush Our Teeth?

Star Wars storm troopers using a large toothbrush

Humans may be no less a part of the animal kingdom than lions, tigers and bears, but certain things set us apart. For instance, although like our mammalian cousins we use teeth to bite and chew food, we're the only animals that brush after every meal.


And as four out of five dentists have reminded us on countless television commercials, using one or another variety of toothpaste is crucial for keeping our teeth healthy.

Like that fifth dentist who never seemed to know what was going on, you might have wondered what toothpaste actually is, and how it helps ward off tooth decay.

What Is In Toothpaste?

Toothpaste consists of several ingredients, some of which you'd never think to put in your mouth. For example, almost all toothpaste contains detergent, or soap. Getting your mouth washed out with soap is supposed to be punishment, so what is it doing in toothpaste?

Although it has a slight antibacterial effect, it's there mainly to make foam, which serves little purpose other than to provide a visual sign to the brusher that the toothpaste is hard at work fighting cavities.


Of course some ingredients play a more active role, the most famous of which is fluoride, a mineral compound derived from the element fluorine. Fluoride protects teeth in two ways: it kills acid-producing bacteria which are mainly responsible for tooth decay, and it strengthens and repairs tooth enamel that has been softened by the acid.

So far as we know, the only drawback to using toothpaste is that it makes drinking orange juice after brushing a pretty unpleasant taste experience. But that's a small price to pay for healthy teeth.

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