Wisdom teeth usually erupt between the ages of 17 to 25. It is the third molar of permanent teeth. There are 4 wisdom teeth, located at the ends of the upper and lower jaws. It is common to have one or more wisdom teeth missing. For some people, their wisdom teeth can normally erupt, while for some others, their wisdom teeth may not successfully erupt and may become impacted.

Photograph of an x-ray film showing a slanted wisdom tooth with its tooth crown pushing the tooth in front, this results in an impacted wisdom tooth.

Cause of impacted wisdom teeth

Wisdom teeth often do not have enough room to erupt because modern human beings have a smaller jawbone. This causes wisdom teeth to grow slanted, horizontally, or even to be completely buried inside the jawbone.

Animation showing normal growth of a wisdom tooth.  The tooth crown can normally erupt and align with the adjacent tooth.
Wisdom tooth
Animation showing abnormal growth of a wisdom tooth.  Its growth is that grows slanted and hindered by the tooth in front, resulting in its tooth crown beingis partially buried inside the jawbone.
Impacted wisdom tooth