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We hope we have all our teeth when we are older. But do you know how many you should have?

How Many Teeth Do Humans Have?

The quickest answer is that we have 20 primary (baby) teeth and 32 secondary (adult) teeth during the span of our lives.

But you have likely been able to tell that they are not all the same shape or size. It’s true and they don’t all serve the same function either.

Types of Teeth

The types of teeth we have include 8 incisors, 4 cuspids (often referred to as canines), 8 bicuspids, 12 molars, and 4 wisdom teeth.

Let’s get to know them a bit more.


Incisors are your first impression - the teeth right in front of your mouth that are noticed first when you smile. There are four incisors on the top row of teeth and four more on the bottom arch. Incisors are usually the first teeth to peek out in infants around six months old, as well as the first to fall out around the age of 6, making room for those secondary teeth to sprout.

The look of incisors have been compared to square pieces of gum, as they are wide and flat in appearance. Incisors function like a chisel in that they break our food into smaller pieces before sending them back to be chewed by other teeth.


Moving back one set from your incisors, there are two cuspids on your top row of teeth and two more mirrored on the bottom. Baby cuspids usually come in between 16 and 20 months old, and the top cuspids often come in first. Conversely, the bottom cuspids will often fall out first to make way for your secondary set, around the age of 9. The cuspids are often called the canines, because they are pointed and sharp looking like that of a dog or wolf. These points have a point! Their sharp edges are effective at tearing up food.


Your bicuspids, also known as premolars, come up next. We have 8 bicuspids, four on the top arch of our teeth and 4 on the bottom. You may be able to see a few bicuspids when smiling, but they are set back and may be covered by the cheeks. Bicuspids are larger than our incisors and canines, but not as large as our molars. These teeth have a flatter surface, but contain ridges that help us grind food into smaller pieces. Unlike the forefront teeth, bicuspids do not come as a primary and secondary set, so they will likely not erupt until around the age of 10. These teeth come in as permanent and will not fall out.


Molars are large teeth located toward the back of the mouth, just in front of your wisdom teeth. We have 12 total molars, with 6 on the top row of teeth, and 6 more on the bottom. By far the most teeth in our mouths! This is likely because they are most useful for chewing food, as they are also the strongest teeth we have. Molars usually show up in the tooth lineup around the age of 6, with the second set arriving around 12 years. You may get a third set in your late teens to early twenties.

Wisdom Teeth

These are the teeth that produce just funny viral videos of people just after removal. Wisdom teeth is actually the term given to your third set of molars, and unfortunately this set must often be extracted to avoid crowding or implactment of the other teeth. If your wisdom teeth are used, which is rare, and they do not overcrowd your mouth, your dentist may recommend keeping them. Otherwise, they will be taken out to avoid pain, swelling, and infection.

Thousands of years ago, humans had larger skulls and tougher diets that required additional chewing power. Nowadays, eating has become easier and our skulls have become smaller than our ancestors. This means that the third molars have problems erupting entirely and can cause problems like pain, swelling, and infection.

Common Dental Issues & How to Prevent Them

Having so many teeth with differing functions helps us to chew, speak correctly, and protect the softer tissues in our mouths. But how do we keep these teeth clean and healthy?

Let’s talk about a few dental issues that could arise in our mouths and get to easy ways to take care of your precious teeth.


Also known as tooth decay, these can affect all of your teeth, but are most likely to affect those precious chompers near the back of your mouth - the molars. The large and rough texture of your molars is a favorite place for cavities to hang out. Here is how it all goes down:

The foods we eat, especially those high in sugar, starch, and acid (foods like cupcakes, candy, chocolate, ice cream, sodas, and juices) cling to our teeth each time we consume them. When not brushed or rinsed away quickly, this food and the bacteria carried in your mouth stick together to create plaque, a sticky stubborn substance that loves to hang out on your enamel, the outermost protective layer of your teeth.

Plaque attacks and erodes your enamel the longer it sits. Plaque wears down your protective enamel as it remains on the teeth and tooth decay begins. If the plaque eats through to the dentin, it can enter into the pulpal center of your tooth and cause major decay issues. This happens as the dentin layer contains open channels that reach from root to enamel. Without protection, your tooth is left vulnerable.

Additionally, if not dealt with quickly, plaque can turn into tartar, an even more stubborn build-up that cannot be removed at home and must be treated by a dentist.

How to Prevent Cavities

If you are noticing dark spots or holes in your teeth, you have a cavity issue that will need intervention by a dentist. However, the process of developing cavities takes time, which means you can help catch and prevent them early-on by doing the following:

Brush Often

The ADA recommends brushing your teeth two times per day, every day, for at least two minutes. That’s easy enough to remember, right? As you brush, make sure not to just scrub off those pearly incisors so they look good. Rather, make sure to give each tooth the attention it needs. Brush lightly, and use a soft-bristled toothbrush to make sure you aren’t hurting your precious enamel. 

Use Fluoride

In addition to just brushing, it is important that you use fluoride toothpaste, as toothpastes without it are unable to provide the protection you need and prevent cavities. Fluoride works by binding with your teeth to cover the enamel and ward off plaque. We love this one by Twice. In addition to it being safe and effective for everyday use, it also does not include any unnecessary ingredients. It’s the perfect start to the day.

Drink Water

Another great way to deter plaque from building up on your teeth is to rinse it often. Water is a great and natural way to wash off unwanted food particles and substances left behind after meals.

Avoid sugary foods. The best way to keep plaque-friendly foods off of your teeth is by avoiding them all together. We don’t expect you to forego that piece of birthday cake you just blew a candle out on, but limiting these kinds of food can be beneficial for the health of all 32 of your teeth.

Gum Disease

As dangerous as plaque and tartar build-up can be for your teeth, they also are dangerous for your gums. As plaque erodes the enamel, it can also be lingering up on your gums. If bacteria is able to rest on the gums without proper care, it can cause swelling, pain and gum recession - all signs of gum disease.

This disease, also known as periodontitis, can cause major issues like tooth abscess, infections of the brain, and even issues in the lungs and heart. Hard to imagine from one little tooth, but it is true.

How to Prevent Gum Disease

Brush along the gums. As you are working on your oral care practice, make sure to brush gently along the gumline. Sometimes we are more focused on making sure our teeth look white that we forget that oral health resides in the gums as well. So make sure to brush away unwanted visitors from your gums and prevent gum disease from happening.


Floss is able to get food particles off of and out from spaces that a toothbrush alone cannot. Make sure to floss at least once a day to keep your teeth and gums healthy and clean.

Use Mouthwash

Like floss, mouthwash is able to get into the smallest places in your mouth and can help loosen and rinse away food particles, while rinsing the teeth as well.

See your Dentist

Not everyone is able to get to a dentist twice a year. So if you are able to, schedule and prioritize your visits and keep all of your teeth clean. If you know how important seeing a dentist regularly is, you will love the work Smile Twice does to give back by providing dental care to those in need.

This page was written or reviewed for accuracy by the Twice Team. Learn more about us.