All About Teeth: 3 Questions About Your Pearly Whites Answered

Do Teeth Have Roots?

They sure do. Below the hard crown is the tooth’s root. It’s tucked away underneath the gum line and tethered to the jawbone by connective tissue called the periodontal ligament.

Most of the root is made of dentin, which forms canals. They hold a living tissue called pulp that’s full of blood vessels and nerves that run through the root of the tooth and into the jawbone.

Can Teeth Feel Sensations?

You might have noticed your teeth feeling sensitive to hot or cold temperatures. This can happen if the root of a tooth is exposed above the gum line, or if enamel wears down. When the dentin that makes up the root is uncovered, the nerves inside can be stimulated by the temperature of the food and drink in your mouth.

The sensations of hot and cold are transmitted through the nerves in the exposed dentin to the brain. Your brain interprets these signals as pain.

This is another reason enamel is so important. It acts like an insulator that shields teeth from extremely hot and cold temperatures. Enamel protects the sensitive nerves in dentin from painful stimulation.

Why Do Teeth Come in Different Shapes?

Take one look at your smile and you’ll know your teeth don’t all look the same. In fact, your teeth vary widely in their shape and size.

While none of the teeth in your mouth are identical, they can be classified by their overall shape. An adult set of teeth has eight incisors, four canines, eight premolars, and 12 molars.

Beginning in the middle and branching out left and right are your incisors. These big front teeth are sharp like a knife. Next to the incisors are the canine teeth. They have a distinctive point called a cusp. They resemble the pointed teeth in dogs.

The next teeth in line are called the premolars. These teeth have two cusps and are sometimes referred to as bicuspids. Finally, the last class of teeth are the molars. They’re large and flat.

What Do the Different Kinds of Teeth Do?

The different shape of each tooth helps it perform a specialized function while you chew your food.

Incisors are great at cutting into and holding chunks of food, like when you bite into an apple. Your incisors can also help you sense the texture of your food.

Canine teeth tear your food into smaller, more manageable pieces. You can put your canines to work by eating a piece of thick protein, like grilled chicken.

The premolars are between canines and molar in shape. Premolars help cut and tear food—much like the canine teeth do.

Molars are used for grinding food. As you chew, pieces of food are moved further back into your mouth where they’re ground up by your molars. Molars help break food into pieces you can swallow safely.