Why our ancestors had straight teeth without braces

Every year, millions of children and teens undergo a common ritual of growing up: getting braces. And it’s not just young folks who turn to metal brackets to handle some common dental issues—the Cleveland Clinic estimates that some 20% of new orthodontic patients are over the age of 18. 

Braces, be it the classic metal brackets, the slightly less noticeable ceramic editions, or even a clear aligner, solve a multitude of problems that many people face, from crowding, to gaps, to crooked teeth. For the 93% of children and adolescents with a crossbite, underbite, or overbite, braces may be just the fix. 

The technology behind braces first came on the scene in the late 19th and early 20th centuries, says Roger Forshaw, dental health expert at the KNH Centre for Biomedical Egyptology at the University of Manchester. In early iterations, metal bands, wires, and rudimentary braces were used to solve severe teeth crowding and misalignments to improve chewing function and relieve pain—hardly the common cosmetic fix we think of today. 

But what did people do before braces were invented? Well, it turns out, for a lot of human history, braces weren’t necessary. And it wasn’t because people were less worried about the way they looked or bore painful chewing better than their modern cousins. It’s a classic case of evolutionary mismatch, a sign of just how much our lifestyle has changed in recent times while the basic hardware of human existence simply hasn’t caught up.

Big jaws, little jaws

Let’s start with a metaphor. Take an old house, says Peter Ungar, a biological anthropologist and evolutionary biologist at the University of Arkansas. Door frames used to be much smaller and lower than would be comfortable for today’s humans, and it’s not because humans were any genetically shorter than today. Instead, people didn’t have the nutrients available to reach their tallest potential, Ungar explains. For our jaws, the story kind of goes in reverse. 

Back in the day, before agriculture and processing food became commonplace, humans had to chew really hard to turn their food into useful calories for their bodies. When you put that kind of chewing stress on the lower jaw (mandible) and upper jaw (maxilla), “it stimulates the cells that produce bone, [known as] osteoblasts, to grow the jaw in both thickness and height and length,” says Ungar. In other words, hearty chewing makes for a strong, full-sized jaw. 

On the other hand, there’s not a workout that will make your teeth grow. Those little pearls of enamel, dentine, and blood vessels have their size predetermined by genetics, he adds. 

Nobody gave teeth the update that modern jaws are chewing less on wild game and more on applesauce, especially in their youth. When teeth grow in, they are expecting a full-grown jaw from a hard-chewing hunter-gatherer. 

So when your teeth finally arrive on the scene, there simply isn’t enough space for them. For many of us, the top row of teeth juts out in front of the lower set, and that lowered set turns into a jumbled pile of cramped teeth. Our third molars, also known as our wisdom teeth, either don’t develop, don’t erupt, or need to be yanked out. Our comparatively small jaws opened the floodgates to all sorts of other issues, Ungar adds, including the sleep apnea epidemic, which occurs when our tongues don’t have enough room to wiggle around in our mouths. 

Embracing braces

Our ancestors had room for every tooth in their larger mouths. Their teeth also lined up more neatly on top of each other. But that doesn’t mean our ancestors had smiles fit for a Colgate commercial. 

“Early humans used chewing sticks, twigs, bird feathers, animal bones, and plant fibers to remove debris from their teeth,” Forshaw adds. “The earliest known example of possible operative dental work dates to approximately 14,000 years ago in northern Italy.”

While there are some references to misaligned teeth, and the likely painful solutions that ensued, in Greco-Roman times, it wasn’t until recently that orthodontics really took off. “Early orthodontic treatments were slow, uncomfortable, and often unpredictable because dentists didn’t fully understand how teeth moved,” Forshaw says.

The first tool to move teeth around via force was Pierre Fouchard’s Bandeau, a horseshoe-shaped metal strip that slowly expanded, straightening teeth as it went. Then came the metal brackets, thanks to E. H. Angle, who first introduced them around 1910. Braces were then tweaked over the following decades as scientists figured out how teeth moved, grew, and best reacted to smile-correcting technology. 

Today, things are a little different, and a great deal less painful, thanks to digital imaging, advanced materials, and less invasive (and less obvious-looking) techniques and tools. From an evolutionary and a modern perspective, the solution to our small-jawed problem starts in childhood. Nonetheless, you probably don’t want your kids gnawing on giant hunks of meat just to save their jaws, which invites a risk of choking. Instead, maybe just get an orthodontist appointment on the calendar around their seventh birthday. 

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