Among the many perplexing mysteries of the mouth is the seemingly late arrival of third molars, or wisdom teeth. Most people develop four wisdom teeth, which emerge sometime in the late teens and early twenties.

How Many Wisdom Teeth Do You Have?

Wisdom teeth are located in the very back corners of the mouth. Though most people develop at least one set, some people never develop any, and others may develop an extra set.

Understanding how many wisdom teeth you have and whether or not you may need them removed is essential for making informed decisions about your care.

When Wisdom Teeth Don’t Show Up

A Harvard University academic review of more than 90 studies involving a total of more than 63,000 participants concluded that the worldwide rate of third molar “agenesis” (which means “without” + “creation”) is 22.63%.[1] In other words, almost a quarter of the population of the world is missing one or more third molars.

The causes behind molar agenesis are still being explored and may involve a combination of factors. The Harvard finding identified a number of interesting trends in the data, including the following:

• Women are 14% more likely than men to be missing at least one third molar
• Missing molars are 36% more likely to be missing from the maxilla (upper jaw bone) in both genders
• Participants were more likely to be missing only one or two of their third molars
• Participants in different geographic areas showed significant differences in agenesis rates

Genetic factors are also thought to play a role in hypodontia, which is another term for the failure of one or more teeth to develop.

In many cases, missing wisdom teeth is an entirely harmless issue that you might never notice. Some dental care providers even consider it an advantage, since wisdom teeth can cause crowding when there isn’t enough room in the mouth. If you’re wondering whether or not you may be missing wisdom teeth, a dental X-ray will provide the answer.

When Too Many Wisdom Teeth Show Up

Extra or “supernumerary” teeth may not be as common as missing teeth, but they still affect 1-14% of people.[4] Research has yet to unveil the cause(s) behind extra teeth, but some theories have been proposed. Some studies show the tooth bud may split into two parts during development, or that extra teeth come from excessive activity of the dental lamina.[5]

Not all cases of supernumerary wisdom teeth present in the same way. Sometimes, they are found positioned at awkward angles (distomolars). They may also be smaller than the wisdom teeth that are crowded behind.

Having extra wisdom teeth doesn’t automatically mean you need surgery. These teeth are often impacted beneath the gums. They don’t usually cause urgent problems, but are monitored by dental care providers after they’re discovered.

Common Third Molar Problems

Whether you have a standard set of four or not, wisdom tooth problems are a highly common occurrence among people across demographics. Wisdom tooth extractions account for a staggering 90% of surgical procedures performed by oral surgeons.[6]

Crowding, which is when these bulky molars push other teeth out of alignment, is just one of multiple issues requiring extraction. Inflammation and infection of the surrounding tissues can also occur when wisdom teeth do not fully emerge through the gums (partially impacted).[7]

When wisdom teeth are fully impacted, they may angle themselves towards adjacent teeth as they grow. Undergoing regular dental checkups is crucial for identifying and addressing the above issues before they cause potentially serious consequences.

Finally, complications related to third molar removal can arise.[8] These include inflammation of the gums, hematoma, difficulty opening the mouth (trismus), and others. While complication risk isn’t tied to age or gender, it does increase in cases involving wisdom teeth with root separations.

The Modern Approach to Wisdom Tooth Care

Contemporary dentistry takes a more conservative approach to wisdom teeth when possible. Some people will require wisdom teeth removal early on, and others may live their whole lives comfortably with a complete set of four. In either case, dental care providers will often look to exhaust more conservative options before resorting to removal.

Factors influencing the decision to remove wisdom teeth included available space (can the jaw accommodate third molars?), oral hygiene (are you able to brush them?), your overall health, and personal preferences.

The Number Doesn’t Dictate the Outcome

Whether you have one, four, or multiple extra wisdom teeth, these categories and all in between still share the exact oral health needs. No amount of wisdom teeth guarantees that you will experience issues requiring extraction.

That said, everyone needs to practice excellent oral hygiene consistently. This means regular brushing, flossing, and regular professional cleanings. There is no reason to stress about having an “abnormal” number of wisdom teeth. Variation is common, natural, and at times even beneficial.

Frequently Asked Questions About Wisdom Teeth