The wisdom teeth grow at the back of your gums and are the last teeth to come through. Most people have four wisdom teeth – one in each corner.

Wisdom teeth usually grow through the gums during the late teens or early twenties. By this time, the other 28 adult teeth are usually in place, so there isn't always enough room in the mouth for the wisdom teeth to grow properly.

Because of the lack of space, wisdom teeth can sometimes emerge at an angle or get stuck and only partially emerge. Wisdom teeth that grow through like this are known as impacted.

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Why are wisdom teeth removed?

Your wisdom teeth don't usually need to be removed if they're impacted but aren't causing any problems. This is because there's no proven benefit of doing this and it carries the risk of complications.

Sometimes, wisdom teeth that have become impacted or haven't fully broken through the surface of the gum can cause dental problems. Food and bacteria can get trapped around the edge of the wisdom teeth, causing a build-up of plaque, which can lead to:

tooth decay (dental caries)

gum disease (also called gingivitis or periodontal disease)

⦁ pericoronitis – when plaque causes an infection of the soft tissue that surrounds the tooth

cellulitis – a bacterial infection in the cheek, tongue or throat

abscess – a collection of pus in your wisdom teeth or the surrounding tissue as a result of a bacterial infection 

⦁ cysts and benign growths – very rarely, a wisdom tooth that hasn't cut through the gum develops a cyst (a fluid-filled swelling)

Possible complications

As with all surgery, there are risks associated with removing a wisdom tooth. These include infection or delayed healing, both of which are more likely if you smoke during your recovery.

Another possible complication is "dry socket", which is a dull, aching sensation in your gum or jaw, and sometimes a bad smell or taste coming from the empty tooth socket. Dry socket is more likely if you don't follow the after-care instructions given by your dentist.

There's also a small risk of nerve damage, which can cause a tingling or numb sensation in your tongue, lower lip, chin, teeth and gums. This is usually temporary, but in rare cases it can be permanent.