Do you know how many teeth you have? Depending on if all of your adult teeth came in, or if you’ve ever had teeth removed or damaged, all adults have roughly the same number of teeth. Teeth are an important part of both your bone structure and your digestion.

Every tooth has three layers: the enamel, dentin, and pulp.

  • Enamel. Enamel is the visible, white, outer layer. This hard surface protects the inner layers of each tooth from the damage of decay or injury. Enamel is the hardest tissue in the whole body.
  • Dentin. This is the middle layer of the tooth, which is the most similar to bone tissue. Dentin makes up the majority of the tooth structure. It has millions of tiny tubes connecting it to the life-source of the tooth: pulp.
  • Pulp. The pulp is the living core of each tooth, and the innermost layer. The pulp is made up of blood and nerves.

The part of the tooth above the gumline is called the crown. And the part of the tooth below the gumline is called the root, which attaches the tooth to your jawbone.

On average, babies first start getting new teeth around 6 months. But it’s not unheard of to see a 3 month old with a tooth, or a 1 year old with just one tooth still. All a child’s “baby teeth” should be in between 2-3 years old.

Baby teeth are also called primary, or deciduous teeth, because they’re temporary and they fall out. A full set of baby teeth is 20 teeth: 10 on top and 10 on bottom.

We get baby teeth because as a child, our mouths aren’t big enough for a full set of adult teeth, but kids still need teeth to chew. So all people are born with both full sets of teeth in their jaw. First come the baby teeth and later, as kids grow older, they lose them and gain their larger, adult teeth one by one.

Even though baby teeth are “temporary,” it’s important that they’re kept clean so that they’re healthy, to maintain lifelong oral health. Tooth decay in childhood can adversely affect adult teeth.

Brush your child’s baby teeth for 2 whole minutes, just as you do your own.

People start losing their baby teeth and getting their adult set as early as 5 years old. Adults have 32 teeth. You should have this full set of adult teeth by your late teens.

Adult teeth include incisors, canines, premolars, and molars:

  • 8 incisors. Your four front teeth on the top and bottom are sharp for holding and cutting food. Incisors also help you sense the texture and kind of food you eat.
  • 4 canines or cuspids. The pointed teeth on the top and bottom are called canine teeth, or cuspids. They have cusps for grabbing and tearing food.
  • 8 premolars. These teeth are between the cuspids and molars both physically and in form. Premolars look like molars but they have two cusps and are sometimes called bicuspids. Premolars cut and tear food.
  • 12 molars. You have eight molars on top and bottom. They have broad chewing surfaces to grind down food before it’s finally swallowed. This includes wisdom teeth, your third set of molars, which can show up as late as your early 20s and are often removed.

Not everyone can comfortably fit all 32 adult teeth in their mouth. Science shows that human jaws began shrinking around the time humans transitioned from hunter-gather societies to sedentary farmers. This could be because the new foods that humans could eat were cooked softer and easier to chew, and thus eating to survive didn’t require a big strong jaw.

Having too many teeth, or overcrowding, can cause:

This is why many people have their wisdom teeth removed.

You get two full sets of teeth over your lifetime. As a baby, you have 20 teeth, and as an adult you should have 32 teeth.

Among the 32 teeth, each has its own function in the chewing and eating process. Take good care of your teeth and keep your gums healthy in order to avoid cavities and other overall health issues.