Wisdom teeth begin to appear from the late teens onwards. Most of us have four wisdom teeth but fewer is not unusual. Some people have none at all.
They erupt last and often there isn’t room. Subsequently they can come through at an angle or pressing against other teeth or bone.

Your dentist can take x-rays to show the position of the wisdom teeth in the jaw and decide if there will be room or if they will need to be extracted. Extractions are often performed by a specialist.

Wisdom TeethSometimes as wisdom teeth are coming through the surrounding gum becomes inflamed and sore, this is 'pericoronitis'. When this condition has happened it can sometimes settle down but it is often better to remove the teeth.
Modern removal of wisdom teeth means no more pain or infection and damage to other teeth or bone stops.