Wisdom teeth usually emerge from your gums between the ages of 17 and 24. They are the last of the large grinding teeth at the back of your mouth. Some people never develop wisdom teeth or you could have up to four appearing – one in each corner of your mouth. For most people, wisdom teeth don't cause any problems and so they don't need to be removed. However, if there isn't enough space for them to grow at the back of your mouth they become 'impacted' wisdom teeth, causing pain, swelling and/or infection. Having your impacted wisdom teeth surgically removed (extracted) can relieve these symptoms.
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