Wisdom teeth usually erupt between the ages of 17 to 25. It's the third molar of permanent teeth. There are altogether 4 wisdom teeth, and they erupt at the end of the upper and lower jaws. It is very common that one or more wisdom teeth are 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.

A. Cause of impacted wisdom teeth

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

B. Consequences of impacted wisdom teeth

1. Pericoronitis
Usually seen in the lower jaw.

Food debris and bacteria are easily trapped in the space between the crown of the wisdom tooth and the overlying gingiva (gum), resulting in the infection of the periodontal tissues (Pericoronitis). Furthermore, the infected, swollen overlying gingiva is often bitten by the opposing tooth making it difficult to recover.

2. Dental Caries
Since it is difficult to clean the surfaces between the impacted tooth and the adjacent tooth in front, dental plaque will accumulate there and cause Dental Caries on these tooth surfaces.

3. Root resorption of the neighbouring tooth
The inflammation of the periodontal tissues caused by the dental plaque, together with the pressure of the wisdom tooth pushing on the adjacent tooth in front, may cause the root of the adjacent tooth to resorb.

4. Causes pathological changes, such as cysts.

C. Treatment

1. If wisdom teeth are completely buried inside the jawbone, nothing needs to be done given that there isn't any symptom.