Our teeth are pretty amazing things, aren’t they? But have you ever stopped to think about just how fascinating they really are? They’re exposed bones that grow in, fall out and then grow in again. They finish developing when we’re in our teens, but with proper care can last the entire rest of our life. The same teeth we get at around age 6 will be with us until we’re 96. Think of all the smiles they’ll make and foods they’ll chew in that time. When you really put it into perspective, teeth are incredible – but believe it or not, they’re even cooler than you may have realized. Teeth and their fascinating history are the subject of a new TED-Ed video by Pete Unger titled “How Did Teeth Evolve?”
“The really cool thing about this video is that it explains that all teeth came from the same ancestor,” says Dr. Stephen Hill, a dentist from Allen, Texas. “It’s called a tribosphenic molar, and it is responsible for the teeth of every mammal – even if they have a very different diet.”
How different? To put it into perspective, the tribosphenic molar first debuted in an animal that’s a pretty far cry from today’s modern human.
“The first tribosphenic molar actually came from a dinosaur,” says Hill.
The video shows not just the genetic history of teeth, but also goes into what teeth are made of: an enamel outer shell and a dentin core.
“The enamel is the material we see when we look at the teeth. Enamel is somewhat translucent and very hard,” says Hill.
Though not directly visible to the naked eye, you can still see the dentin, too.
“Many people don’t realize it’s the dentin that’s responsible for your tooth color, not the enamel,” says Hill. “So, when your teeth are stained, it’s because a stain has gotten through to the dentin. That’s also why it’s so hard to successfully whiten your teeth.
“The dentin is not quite as hard as the enamel. It’s probably about as hard as the rest of the bones in your body,” says Hill. “Its purpose is to protect the pulp of the tooth, but it also supports the enamel that coats it. And that’s true for every mammal alive today.”