Wisdom teeth are the upper and lower third molars , located at the very back of your mouth. They are the last teeth to surface in the mouth. They are called wisdom teeth because they usually come in when a person is 17 to 21 years old—old enough to have gained some "wisdom."

Some people have their wisdom teeth for their entire lives. Other people choose to have their wisdom teeth removed, sometimes before these teeth have broken through the gums.

If your jaw is not big enough to make room for your wisdom teeth, they may get stuck (impacted) in your jaw and not be able to break through your gums. An impacted wisdom tooth can crowd other teeth and create painful, swollen, and infected flaps in your gums.

Wisdom teeth that have broken through your gums may cause cavities and gum disease, because they can be hard to clean.

Sometimes a cyst can form that can damage the bone or roots.

Most problems with wisdom teeth happen when a person is 15 to 25 years old. Few people older than 30 have problems with their wisdom teeth that require them to be removed.

Most dentists feel that if you're 16 to 19 years old, you should have your wisdom teeth looked at.

Some dentists and oral surgeons think it's best to have impacted wisdom teeth removed (extracted) before you're 20 years old, because it's easier to take them out when the roots and bones of your teeth are softer and not fully formed. As you get older, the bones around your teeth grow and get hard. This makes it harder to remove the teeth. And when you're older, it may take longer for you to heal after you have had them removed.

After you have your wisdom teeth removed, you may have:

• Pain and swelling in your gums and tooth socket where the tooth was removed.
• Bleeding that won't stop for about 24 hours.
• Problems or pain when you try to open your jaw. This is called trismus.
• Slow-healing gums.
• Damage to dental work, such as crowns or bridges, or to roots of a nearby tooth.
• Dry socket, which causes pain and swelling and occurs when the blood clot that protects the open tooth socket is lost too soon.
• Numbness (freezing) in your mouth and lips after the local anesthetic wears off or because of an injury or swelling to the nerves in your jaw. Numbness usually goes away. But in rare cases, it may not.
• An opening into your sinus cavity if a wisdom tooth is removed from the upper jaw.

There is a small risk of death or other problems whenever a general anesthetic is used.

The decision to have your wisdom teeth removed if they're not impacted has to be weighed against the risks and benefits of having them removed.

Problems may occur if you don't have your wisdom teeth removed. For example:

• When there isn't enough room in your mouth for your wisdom teeth to come in, they may get impacted and never break through your gums.
• Your wisdom teeth may break through your gums only partway, causing a flap of gum tissue to grow over them. Food can get trapped under the flap and cause your gums to become red, swollen, and painful.¹ These are signs of an infection.
• One or more of your wisdom teeth may come in at the wrong angle. The top of the tooth may face forward, backward, or to either side.
• Impacted teeth can cause infection and damage to your other teeth and bones. A fluid sac may form around an impacted tooth, and the sac may grow into a cyst. This could cause lasting damage to your nearby teeth, jaw, and bones.
• Your risk of getting cavities and gum disease in the back of your mouth is higher if you keep your wisdom teeth, because it's hard to brush and floss that part of your mouth well. But if you visit your dentist once or twice a year, these problems can be found and treated early.
• Your wisdom teeth may cause problems with future orthodontic treatment.

Your dentist may suggest that you have your wisdom teeth removed if:

• They cause pain or an infection.
• They crowd other teeth.
• They are impacted.