Wisdom Teeth: When Should They Come Out?

Contrary to popular belief, not everyone has to have their wisdom teeth removed (or even gets them, for that matter).
Contrary to popular belief, not everyone has to have their wisdom teeth removed (or even gets them, for that matter).

By the time you're about 13 years old, you should have 28 permanent, or "adult," teeth. Your pearly whites may not have quite finished coming in, though; between the ages of 17 and 25, some people also have up to four more teeth making an appearance. They're so far back in the jaw that you may not have even realized it was happening until the dentist pointed it out. Known as wisdom teeth, or third molars, these teeth have the potential to cause serious issues, including pain, infection or damage to other teeth around them. If wisdom teeth are such troublemakers, then why do we have them in the first place?

Wisdom teeth are a sort of evolutionary relic known as a vestigial structure -- a part of our bodies that once served an important purpose but whose original function has either diminished or completely changed over time. Wisdom teeth are unique, however, because unlike other vestigial structures like the appendix, we don't all get them (about 35 percent of the population doesn't, in fact [source: Spinney]). For some folks, they erupt and cause no problems -- maybe other than the fact that they're so far back they can be difficult to keep clean. For others, just the phrase "wisdom teeth" uttered by their dentist seems to set off waves of pain and swelling.


There are two potential reasons for our wisdom teeth's vestigial nature. Our ancestors probably needed the additional molars to help grind tough food for easier digestion. The jaws of homo neaderthalensis, or Neanderthals, were much larger and stronger than ours; they even had a space behind these third molars called the retromolar gap. The hominid jaw shrunk with the evolution of homo sapiens (modern humans) as we began eating a softer diet, but the wisdom teeth still erupt even when there isn't space for them.

Our modern dental practices may also be to blame. Thousands of years ago, it was common for hominids to have lost some teeth to decay by the time they were teenagers, so additional pairs would've been useful. Teeth straightening also exaggerates modern humans' dental arch (the way that our side teeth splay outward in our jaw instead of being parallel like Neanderthals'), leaving even less room for wisdom teeth.

It was once practically a rite of passage for a teenager or young adult to get their wisdom teeth "cut out," but today, not all dentists support removing them immediately. Learn about the pros and cons next.


Wisdom Teeth Complications and Removal Controversy

When wisdom teeth erupt in an abnormal position due to lack of space, it's known as an impaction, and it can be nasty. Impacted teeth can grow in at an angle or even end up completely horizontal. Wisdom teeth can also break through partially, leaving a flap of gum over the top (which allows debris and food to become trapped inside). Sometimes the tooth never fully emerges, remaining wedged between the jawbone and the gum. Any of these scenarios can result in infections and damage to surrounding teeth, gums, bone and nerves. Sometimes a cyst forms around the tooth; left untreated, this can lead to tumors in rare cases.

Because of the potential for problems, many dentists recommend pre-emptive third molar removal. The American Academy of Oral and Maxillofacial Surgeons (AAOM) states that even if you don't feel pain, wisdom teeth can still cause damage, and leaving them could increase your risk of developing periodontal disease later in life. It strongly recommends that wisdom teeth be removed in young adults. The younger you are when they're removed, the easier the surgery will be, because your jawbone is softer and the teeth's roots haven't yet fully developed. Sometimes the roots can extend to nerves in the jaw, making the extraction more complicated. That's why most people who have their wisdom teeth removed do so between 16 and 18 years old.


The American Dental Association takes a more neutral stance, stating that "wisdom teeth are a valuable asset to the mouth when they are healthy and properly positioned" [source: American Dental Association]. The American Public Health Association is strongly against the removal of third molars -- even impacted ones, if there are no symptoms -- calling it "non-evidence based." Where your dentist went to school may also make a difference in his or her recommendation; for example, North American dentists usually recommend removal, while South American dentists are less likely to do so.

Wisdom tooth extraction surgery comes with risks of its own. In addition to the potential for complications from anesthesia, you can also experience temporary or permanent damage to nerves in the jaw, the joints or surrounding teeth. Recovering from the surgery typically means spending a few days of spring or winter break with a painful, swollen jaw; bleeding, oozing areas; and a diet of soft foods like Jell-O.

So the question isn't just when wisdom teeth should come out, but whether they should come out at all. The only person who can answer that question is the patient (and his or her parents), taking the advice of a dentist into consideration, of course.


Lots More Information

Related Articles

  • American Academy of Oral and Maxillofacial Surgeons. "Wisdom Teeth." AAOMS. 2008. (Aug. 10, 2011) http://www.aaoms.org/wisdom_teeth.php
  • American Dental Association. "Wisdom Teeth." ADA Oral Health Topics. 2011. (Aug. 11, 2011) http://www.ada.org/2988.aspx
  • American Public Health Association. "Opposition to Prophylactic Removal of Third Molars (Wisdom Teeth)." APHA Policy Statement Database. Oct. 28, 2008. (Aug. 10, 2011) http://www.apha.org/advocacy/policy/policysearch/default.htm?id=1371
  • Mayo Clinic Staff. "Impacted wisdom teeth." Mayo Foundation for Medical Education and Research (MFMER). April 11, 2011. (Aug. 10, 2011) http://www.mayoclinic.com/health/wisdom-teeth/DS00679
  • MedicineNet. "Dental Health and Wisdom Teeth." MedicineNet.com. 2011. (August 10, 2011) http://www.medicinenet.com/wisdom_teeth/article.htm
  • Spinney, Laura. "Vestigial Organs: Remnants of Evolution." New Scientist. May 17, 2008.
  • Zadik, Yehuda and Liran Levin. "Decision Making of Israeli, East European, and South American Dental School Graduates in Third Molar Surgery: Is There a Difference?" Journal of Oral and Maxillofacial Surgery. April 2007. (Aug. 10, 2011) http://www.sciencedirect.com/science/article/pii/S0278239106016697