Third molars or commonly referred to as wisdom teeth are the last teeth to erupt in the mouth. In the mouth, there are four wisdom teeth, two in the upper arch and two in the lower. Wisdom teeth may not erupt or emerge from the gums until late teens or early twenties – if they erupt at all. Most often they are impacted or trapped in the jaw-bone and gums, usually because there is not enough space for them in the mouth.
Wisdom teeth are removed for two general reasons: either the wisdom teeth have already become impacted, or the wisdom teeth could potentially become problematic if not extracted. Potential problems caused by the presence of grown-in wisdom teeth include infections caused by food particles easily trapped in the jaw area behind the wisdom teeth where regular brushing is difficult or ineffective. Such infections may be frequent, and cause considerable pain. Other reasons wisdom teeth are removed include misplacement of tooth which rubs up against the tongue or cheek causing pain and potential crowding of the remaining teeth.