Your teeth are calcified structures in your mouth that help crush and break apart food, so it is easier to swallow and digest. They are an important part of your digestive system. Teeth also help you form words when speaking.

In this article, we’ll review when teeth come in, different types of teeth, what they’re made of, and how you should care for them.

When do teeth come in?

During a lifetime, most people have two full sets of teeth:

• Baby teeth typically begin to emerge at 6 to 12 months old, with all of them in place around age 3.
• From the ages of 6 to 14, baby teeth will fall out and be replaced by permanent adult teeth. 

Most of your adult teeth will emerge by age 13 or 14. The exception are wisdom teeth — they often erupt between ages 17 and 21, but it is also common for them to become impacted, which means that they never, or only partially, emerge.

How many teeth do people have?

In your lifetime, you will typically have 20 baby teeth and 32 adult teeth, including your wisdom teeth.

What are the types or names of teeth?

Not all teeth are the same. They come in different shapes and sizes and serve different purposes. Types of teeth include:

• Incisors: The middle teeth on both the upper and lower jaws — four on top and four on bottom. They have a narrow edge to help you cut into foods when you bite.
• Canines (cuspids): These four teeth are located on either side of your top and bottom incisors. Their pointy tips help tear and rip apart meats, crunchy vegetables, and other tough foods.
• Premolars (bicuspids): Your eight premolars sit between your canines and your molars. They help move food from the front of your mouth to the back, and their flat surface grinds down food when you chew.
• Molars: Your eight molars are located near the back of the mouth. They have a large, flat surface area that grinds down food so it can be easily swallowed and digested.
• Wisdom teeth: Your four wisdom teeth are in the very back of your mouth. They are technically molars, but they’re often thought of separately because they erupt later (or not at all) and are often removed by surgery if your mouth does not have room for them.

What are the different parts of a tooth?

Your tooth is made up of a few main parts:

• Crown: This is the top part of your tooth, used to bite and chew food.
• Neck: This is the area of the tooth between your crown and root.
• Root: These are hidden inside of your gums and anchor your teeth to the jawbone, so they stay in place.

What are teeth made of?

Each tooth includes the following four main layers of hard and soft tissue:

• Dentin: Most of your tooth is made up of this slightly yellow tissue, which is the layer beneath your enamel.
• Enamel: A hard, thin coating that makes up the visible outer layer of a tooth.
• Cementum: While enamel covers the dentin on the crown of the tooth, this hardened tissue is the layer that covers the dentin on root surfaces. Cementum is not as strong as enamel, but it helps hold your teeth in place by connecting to fibers in your jawbone.
• Tooth pulp: Located right in the center of your tooth, this soft, sensitive tissue includes nerves and blood vessels.

Are teeth bones?

Your teeth and bones are not the same, even though they are both white, hard, and need calcium to thrive.

Bone is living tissue made from collagen (a type of protein) and calcium phosphate (a mineral), while teeth have multiple layers of hard and soft tissue as described in the previous section.

One big difference is that bones can heal themselves, but teeth usually cannot — which is why it’s so important to keep your teeth clean, strong, and healthy!

How should you care for your teeth?

Caring for your teeth is not difficult, but it does require daily attention and a little bit of planning. To protect your smile:  

• Brush twice a day with a fluoride toothpaste.
• Floss daily.
• Use mouthwash.
• Visit your dentist for regularly scheduled checkups.
• Eat a nutritious, well-balanced diet.
• Drink water instead of sugary or acidic beverages.
• Wear a mouth guard while playing sports and physical games.

It’s important to visit your dentist for regular check-ups and cleanings. Some problems that can develop if you skip your check-ups are:

• Bad breath
• Dry mouth
• Gum disease and tooth loss
• Sensitive teeth
• Cavities and tooth decay
• Tooth abscess
• Cracked teeth

Your teeth are built to last.

Your adult teeth are meant to last you a lifetime — but only if you take great care of them. By practicing good oral health habits, you can help protect your smile for years to come.