Calculus is the dental word for plaque that hardened into tartar.

In kid words

Calculus is plaque that stayed on your tooth so long it turned hard, kind of like a barnacle stuck on the bottom of a boat. Once it gets that hard, your toothbrush can't scrub it off anymore. That's why your hygienist has special tools just for the job, so your teeth end up smooth and clean again.

The parent version

Calculus, also called tartar, is plaque that has hardened onto the surface of a tooth. Plaque itself is soft, and daily brushing and flossing are built to clear it away before it has a chance to set. Once it hardens into calculus, though, a toothbrush at home can no longer remove it.

This isn't a sign that anything went wrong. It's simply how plaque behaves when it sits undisturbed, and it happens to grown-up teeth too. It's also one honest reason routine professional cleanings exist: to clear away what brushing at home cannot reach or budge. How quickly it builds up varies from child to child, so ask your pediatric dentist what your own child's teeth tend to need.

Where you might hear it at our office

This word tends to come up during a routine cleaning and exam, where the hygienist clears away plaque and the hardened buildup a toothbrush cannot reach, then polishes teeth smooth again. Regular visits give calculus less chance to build up between cleanings.

If another word from a visit is still a mystery, the rest of the dictionary is right here.

Related words

Words that often come up alongside calculus: plaque, tartar, cleaning.