Is There an Evolutionary Reason Why Teeth Are So Fragile?

Have you ever wondered why teeth don’t repair themselves like cuts or scrapes on your skin, or broken bones? Why don’t they regenerate themselves like fingernails or hair? In this brief article, we will summarize what science has to say about that question.

man baring his evolutionary determined fragile teeth

“Damage Threshold”

Almost all organs in the human body have a high “damage threshold,” meaning that it is capable of repairing or re-growing itself using materials supplied by the body, even after sustaining significant damage. But such is not the case with teeth. Although the body is capable of producing two separate sets of teeth during childhood, and adding additional “wisdom” teeth later in life, teeth have a very limited ability to be repaired by natural means.

The Role of Enamel

“Human teeth are covered with a hard cap of enamel that forms from the inside out,” explains Peter Ungar, dental anthropologist at the University of Arkansas. “The cells that make the cap move outward toward the eventual surface as the tooth forms, leaving a trail of enamel behind. If you’ve ever wondered why your teeth can’t grow or repair themselves when they break or develop cavities, it’s because the cells that make enamel die and are shed when a tooth erupts.” Ironically, the only thing capable of damaging teeth by natural means is the acidic bacteria in the food that teeth chew.

Why Do Our Teeth Have Such a Low Damage Threshold?

The apparent reason is because we evolved the ability to generate an entire set of adult teeth, and to generate subsequent wisdom teeth which our ancestors needed, which seems to have prevailed over the evolution of teeth that could self-repair.

If your teeth have surpassed their “damage threshold,” or if it’s just time for your checkup, don’t hesitate to set up an appointment with our dentist today.