Teeth Types and How Many Teeth Do Humans Have (2025)

Human Teeth Overview

Your teeth aren't all the same. When you look at your dental records or hear your dentist talk, you may notice several different names for your teeth.

A full set of adult teeth include:

• 8 incisors
• 4 cuspids (canines)
• 8 premolars
• 12 molars

Teeth come in four main types. Each type sits in a certain part of your upper and lower jaw and plays a unique role. The top and bottom rows are aligned so you can bite and chew your food. When your mouth is closed, your bottom teeth fit just inside the top teeth.

Teeth also change over time as baby teeth fall out to make room for adult ones. Then after all the baby teeth fall out and the permanent ones come in, you might still undergo another change. Around this time, many people have surgery to remove their wisdom teeth.

Although you may not think about them often, your teeth help you smile, speak, and chew food. Here are some details about your teeth you may or may not have considered.

What Are the Types of Teeth and Their Functions?

You have four types of teeth, which include:

1. Incisors
2. Cuspids (canines)
3. Premolars
4. Molars

There are eight incisors -- four on top and four on bottom. These sharp teeth sit at the front of your mouth, and you use them to take your first bite of food. They also cut food into smaller pieces to make it easier to chew. These “front teeth” help you talk, especially to pronounce letters such as “t” and “l.” They also play a big part in your smile. The two middle teeth are called central incisors and the ones on either side of them are known as lateral incisors.

Next, you have four cuspids -- also called canines -- two on top and two on the bottom. These pointed teeth at the front corners of your mouth resemble those in meat-eating animals such as wolves and tigers. You use them to rip and tear food. They are your longest teeth. These are called canine teeth because of their position, shape, and function.

Further back in your mouth are eight premolars -- four on top and four on bottom. These flat, ridged teeth sit behind your canines on the sides of your mouth. Also known as “bicuspids,” they tear and crush food.

Finally, your molars line the back of your mouth where they chew and grind food. They're your largest teeth and have a flat surface with ridges. Also known as “6-year molars” or “12-year molars,” the first and second molars tend to come around those ages. Their main use is to crush food until it's small enough to swallow.

There's a third type of molar called wisdom tooth. Four come in last at the back corners of your mouth. Some people crowd the mouth and cause problems with the gums or jawbone. Sometimes, these are “impacted,” which means they can't break through the gums and there's no room for them in the mouth. Many people have surgery to remove these teeth in their teens or 20s.

Your Two Sets of Teeth

You have two sets of teeth. The first is called primary teeth and grows by the age of 2. The second set is called permanent teeth. These grow between the ages of 6 and 12. You start with 20 primary teeth and end with 32 permanent teeth, including the four wisdom teeth.

The lower central incisors are typically the first to arrive when babies turn 6 months old. Among the permanent teeth, the upper and lower first molars are usually the first to come in when kids are 6. They emerge behind the last primary teeth. Most adult teeth come in by age 12. Tooth growth is considered complete only when roots are fully formed, which is around the age of 16. Wisdom teeth grow between ages 17 and 25.

How Many Teeth Do Humans Have?

Children start with 20 milk teeth. Their jaws grow making more space for the 32 teeth that adult humans have in total. Some people may have extra teeth, a condition known as hyperdontia; however, a majority of people have less than 32, because most people have at least one or more of their wisdom teeth removed.

You may notice your dentist or dental hygienist count your teeth or look at a chart that has numbers on it. The American Dental Association (ADA) created a teeth chart with a numbering system that assigns a number from 1 to 32 to permanent teeth (including wisdom teeth) and a letter from A to T to primary teeth.

In adults, number one is the top rightmost molar in the back, which is the top right wisdom tooth. The numbers go around the top of the mouth so that the top left wisdom tooth is number 16. Number 17 is the bottom left wisdom tooth. The numbers continue around the bottom and end with 32 for the bottom right wisdom tooth. Similarly, in children, the alphabets start with A for the top rightmost molar and ends with T for the bottom rightmost molar.

The following are the primary teeth chart, including the alphabets assigned to them, eruption and falling ages, and permanent teeth eruption age and teeth numbers charts:

What Are the Structures of Teeth?

Your teeth have several parts:

• The crown is the visible part of your tooth.
• The enamel is the protective layer on the crown.
• The dentin is inside the tooth and is not visible. Still, though, it is the largest part of your tooth.
• The pulp contains nerve endings and blood.
• The root is under your gums. It anchors your tooth to your jawbone.

Frequently Asked Questions (FAQs) About Teeth Types

How often should you see the dentist for a checkup?

The American Dental Association recommends ideally one should see a dentist once every six months for a checkup and cleaning, or at least once a year. Some people may need to see a dentist as often as every 3 months if they have oral health issues such as gum disease. People who follow good oral hygiene and do not have any dental problems may go to a dentist less often, but it is best to go for regular checkups and cleaning for preventive care. The earlier a problem is identified, the easier it is to treat and prevent complications.

How many teeth does a child have, and when do they lose them?

The first tooth appears when a child is around 6 months old, and the child has the complete set of 20 milk teeth before the age of 3 years. These last until the age of 6 years when they start falling one by one until the age of 12. The permanent ones start to erupt at 6 years of age pushing out the milk teeth, and by 13 years of age 28 permanent ones would have erupted. Children's jaws grow to accommodate more teeth. By age 16, the roots of the permanent teeth would have fully developed, and an adolescent would have 28 permanent teeth.

What is the total number of teeth in an adult human?

The total number of teeth in an adult human is 32, including the wisdom teeth, which are the third set of molars. However, very few adults have 32 teeth; most people only have 28, because they have their wisdom teeth extracted. Other reasons for tooth loss are advanced age, and dental, oral, and/or gum diseases.

The wisdom teeth usually erupt at 17 to 21 years of age and complete growth by 19 to 23 years of age. In many people, one or more of the wisdom teeth may not erupt at all, or erupt improperly. or get impacted in the gums or jawbone. This can cause problems such as infection, tooth decay, and pain. Most people have at least one, or all of their wisdom teeth removed.

What are the names of the types of teeth in adults?

The names of the types of teeth in adults are incisors, canines/cuspids, premolars/bicuspids, and molars. Children with primary teeth don’t have premolars, only two sets of molars which are replaced by permanent premolars, and in addition, grow three sets of molars as they grow into adulthood.

How are the teeth names related to their functions?

Teeth are named after their shapes and functions. These names originate from the Latin words for their shapes and/or functions.

• Incisors: Incisors are the sharp teeth in the front that cut, or “incise.” They are usually the first teeth we use to bite into chewable pieces.
• Canines/cuspids: Canines help tear off the piece of food bitten by the incisors. They are pointed and have the longest teeth. They are called canines because they are similar in function and position to the “fangs” in dog and cat families. The medical term is cuspid, meaning a tooth with a point.
• Premolars/bicuspids: Premolars have two points (bicuspid). They have characteristics similar to both canines and molars, and they help in tearing up the food as well as grinding it into smaller pieces. They also guide the food back towards the molars.
• Molars: The word “molar” comes from “milling” or “grinding.” Molars are wide and concave with ridges, and can crush and grind the food to a pulp, ready for swallowing. The third set of molars are the last ones to grow, and are called wisdom teeth, possibly because they grow at a later age when one is presumably “wiser.”

What is the eyetooth in humans?

The upper two canines are sometimes called the eyeteeth. They probably got this name because they are directly aligned to the eyes and have the longest roots going up towards the eye orbits. Colloquially, the term, “to give one’s eyetooth,” is used to mean that one is willing to give any precious thing to acquire something one desires to possess.

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