Wisdom teeth, also called third molars, often are extracted either before or after they come in.
They commonly come in during your late teen years or early twenties. Impacted teeth get stuck in the jaw and often need to be removed if they are decayed or cause pain.
A wisdom tooth that has emerged partially may be blocked by other teeth or may not have enough room to come in completely. This can irritate the gum, causing pain and swelling, which requires the tooth to be removed.