In the far corners of our mouths, buried at least until young adulthood, lies an ongoing mystery.

Wisdom teeth, also known as the third molar or M3s, serve little to no obvious purpose in modern life and often cause us trouble when they become impacted or crowd the other teeth. And yet the great majority of humans have them. Why?

It is said that about 95 percent of the population has wisdom teeth – and an estimated 90 percent develops at least one impacted wisdom tooth, according to the American Association of Oral and Maxillofacial Surgeons. Impacted wisdom teeth need to come out, or else pain and infection will result. In the United States, that typically means a visit to the oral surgeon, who is best qualified to remove the third molars and restore basic function to the teeth and jaws.

Although it’s up to oral surgeons to fix the problem, understanding why the problem exists is not their expertise. For that, science turns to anthropologists – who study ancient skeletons and piece together how humans have evolved over the millennia – and geneticists, who can find clues to evolution at the molecular level.

Among anthropologists, the dominant theory is that early humans once needed those extra molars to help chew the tough, uncooked foods that our ancestors lived on, such as roots, nuts, and raw meat. Jaws were more pronounced back then, and the much-needed M3s fit just fine back there and got the job done.

More recently – not so long ago in geologic time – humans learned to cook their food, making it softer and easier to digest. And as brain size grew, jaw size shrank, leaving wisdom teeth as the unwanted extras. Or so goes the theory.

Meanwhile, geneticists have identified a specific gene, MYH16, which appears to be connected to brain size and characteristics of the jaw – although its exact role in human evolution has not yet been pinned down.

The theories behind wisdom teeth may be interesting. But at a practical level, someone suffering from an impacted third molar will be much more interested in getting it extracted quickly and safely – and that’s where oral surgeons come in.

If you have an impacted tooth or have any questions about any oral surgery procedure, please call Utah Facial & Oral Surgery to make an appointment today!