How Your Teeth Work: A Quick Guide to Your Pearly Whites

We see them every day. They do lots of work for us when it comes to eating food, gnawing on pens while thinking, or giving an enthusiastic and beautiful smile.

Teeth are something we notice each day, several times a day. But how much do you really know about those small yet essential things in your mouth?

We think knowing how your teeth function can help you realize their importance, which means you will take better care of them (and avoid more trips to the dentist!)

Anatomy of a Tooth

Your mouth, as an adult, is full of around 32 teeth. You probably received your last adult tooth before or around the age of 12.

A tooth in and of itself is a fascinating thing. There are two basic parts of a tooth: the crown (the visible part) and the root (the part that goes below your gum line).

The hard white substance that makes up the outside of the crown is called enamel. Enamel is one of the hardest substances in the human body, even harder than bone, believe it or not. It takes a lot to wear through it, but if you eat or drink acidic things or don’t brush and floss regularly, you can get holes – cavities –  in your enamel.

Below the enamel is the dentin. Dentin is made of the same calcified substance as bone. It basically serves as a second line of defense. It is not as durable as enamel, though, so it is even more vulnerable to decay.

At the center of your teeth is the pulp. The pulp is the soft tissue that contains the blood vessels and nerves that help keep your teeth alive.

Finally, on the outside of the root is cementum. This tissue is fairly soft compared to the rest of your tooth and helps anchor the root to the bones around your mouth. It is important to take care of your teeth and gums, because if you don’t, the cementum can become exposed to harmful bacteria and lead to serious problems.

These are what a tooth is made up of! Your 32 teeth are divided into four basic categories, which we’ll go over.


Let’s start with the most noticeable ones: the incisors.

Incisors are your front teeth. You know the Christmas song lyric, “All I want for Christmas is my two front teeth?” When we sing it, we are talking about our incisors. There are eight of them, four on top and four on the bottom. They tend to be the first baby teeth to come in and the first to go when a kid grows up, which is why kids have those adorable toothless smiles when they’re around the age of 6 just before their adult incisors arrive.

Incisors are needed to bite into food. Without them, you will have a hard time biting into anything.


No, you don’t have dogs in your mouth. Your canines are the four teeth – two on the top, two on the bottom – on either side of your incisors. They are your sharpest teeth, and they’re designed to tear and rip food as you chew it. (If you’re a vampire, you’ve used them for other purposes.)

They come in anywhere from age 9 (for upper canines) to age 12 (for lower ones).


Your premolars (they’re also called bicuspids) are found on each side of your mouth, next to your canines. There are eight total: four on the upper row and four on the lower. (The mouth is a very symmetrical thing, in case you couldn’t tell.)

Premolars help you grind and chew food. They show up around age 10.


Your permanent molars also help you grind and chew food, and are located on both rows. There are eight total, four up and four down. They tend to start coming in around age 6 for the first permanent molars and age 11-13 for the second permanent molars.

Wisdom Teeth: Another type of molar includes your wisdom teeth. There are four total wisdom teeth, two on the top and two on the bottom. They are in the very back of your mouth, and it is really hard to see them. If they come in normally – or don’t come in at all – it’s no big deal, but if they do not fully erupt, or if they start crowding your other teeth, they’re usually taken out.

Your teeth are really cool, and really important. Take good care of them by brushing and flossing regularly and going to your dentist for checkups. Your teeth will thank you!