When wisdom teeth need to be taken out
BMJ Group Medical Reference
Wisdom teeth are impacted if they don't come through the gums properly. It's not always easy to tell whether impacted wisdom teeth need to be taken out.
But experts agree that an impacted wisdom tooth should be taken out if it's causing problems. The most common problems are: 
An infection around the tooth
Damage to a neighbouring tooth
Decay (a cavity) in the tooth that the dentist cannot treat
A cyst (a sac filled with fluid) in your jaw.
If you do need to have one or two of your wisdom teeth removed, it doesn't mean that you must have all of them taken out.
Your dentist may be able to do this operation. It all depends on how easy or difficult each tooth is to remove. Upper wisdom teeth are often easier to take out than lower ones. If there's any chance of complications, you'll probably be sent to an oral surgeon. This is someone who specialises in surgery on the mouth.
To read about what to expect if you have surgery, see Removing impacted wisdom teeth that aren't causing problems.
An oral surgeon is a professional who is trained in both dentistry and surgery. Oral surgeons do operations on people's mouth, face or jaw.
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