Most people are very familiar with wisdom teeth. You or someone you know, has already removed his or her wisdom teeth, or is advised to do so in the future. But when I talk to my surroundings, most of my patients or my friends don’t know precisely why dentists extract wisdom teeth. Some even mistake the reasons why those teeth need to be removed.

Wisdom teeth are the third molars and the last teeth in the jaw of the set of adult dentition. I thought a summary on wisdom teeth was needed to clear some little mysteries about them.

They will not cause other teeth to move

Despite popular belief that if you keep your wisdom teeth they will make the rest of your teeth crooked, this concept is not proven by science. Research is showing that teeth may move in a natural way, even if wisdom teeth are not present. Therefore crowding can develop naturally in adult teeth, whether or not you have wisdom teeth.

Even if there is missing space in the jaw, extracting wisdom teeth for the only reason to prevent other teeth from being crooked would be totally inappropriate.

Why are they called wisdom teeth?

Wisdom teeth, being the third molars and the last of the series of teeth, they come out the last. Their eruption, if they don’t stay impacted, occurs at around the age of 17 to 25 years old. It’s a time of life that a person reaches a wise age, and that is why those molars are called wisdom teeth.

Some people don’t have them at all

Dental agenesis is the developmental absence of one or more teeth. Also called hypodontia, or congenitally absent teeth, it occurs at an approximate rate of 25% of adult teeth. Wisdom teeth are the most affected by dental agenesis.

This means that some people might have a missing wisdom tooth because it has never developed in their jaws. More rarely a person can have all 4 wisdom teeth missing. Of course, this doesn’t affect their level of wisdom and intelligence!

Some people don’t need to extract them

If a person has a lot of space in their jaw, there is a possibility that wisdom teeth will erupt normally and might not need to be extracted. Wisdom teeth do not need to be removed if they are healthy, fully erupted, functioning properly, and correctly positioned in accordance to neighbouring teeth.

In this case, wisdom teeth will need more effort for oral hygiene, as they are hard to reach. It is important to brush and floss them to avoid tooth decay and gum disease. There are cases when wisdom teeth have erupted normally, but still needed to be removed because of problems due to lack of oral hygiene.

They may cause damage if they stay impacted

There are situations where wisdom teeth do not end up in a healthy position, especially if they stay impacted, or partially impacted, in the jaw.

Cases where wisdom teeth need to be removed:

  • if they stay completely impacted in the jaw, which means that they are trapped inside and hidden, and can only be seen on a panoramic x-ray; this can create a cyst or infection, which may damage the jaw bone, or the roots of neighbouring teeth;
  • if they erupt partially through the gums; because that area would be hard to clean, wisdom teeth that only partially come out create a passageway for bacteria that would cause gum disease, tooth decay, and oral infections;
  • if they have erupted completely but, because they are harder to clean, they are colonized by bacteria and have either advanced cavities or gum disease.

References

  1. Talk Dentist, Wisdom teeth.
  2. De Coster PJ, Marks LA, Martens LC, Huysseune A. (Dental agenesis: genetic and clinical perspectives). J Oral Pathol Med. 2009 Jan;38(1):1-17.
  3. Takehiko S, Takahide M. (Prevalence and genetic basis of tooth agenesis). Japanese Dental Science Review, Volume 45, Issue 1, May 2009, Pages 52-58.