We have two sets of teeth in our lives: baby teeth and adult teeth. But wouldn’t it be nice if we grew three sets instead of just two? Imagine if all our adult teeth fell out when we reached middle-age, and then a new set of adult teeth grew in to replace them. Our diseased, decayed and damaged teeth would be gone, and in their place, we would have a new set of perfect teeth. Sounds good, right?
Teeth Renewal in the Animal Kingdom
Three sets of teeth isn’t just the stuff of science-fiction. Many animals already have the ability to grow new teeth. For example, sharks renew their teeth as fast as every three weeks. For this reason, scientists suspect the sea floor may be littered with sharks’ teeth!
Elephants also regenerate their teeth throughout the lives. This is because of their diets; their teeth wear down very quickly due to a chewy diet of leaves, branches and tree bark.
Most amphibians and reptiles and can also grow new teeth. Mammals, on the other hand, have the short end of the stick: typically they only have one set of adult teeth.
Why can’t humans regrow teeth?
Many people nowadays suffer from cavities and gum disease. It’s quite rare for someone to have perfectly healthy teeth. But this wasn’t always the case. Hundreds of years ago, people usually had very healthy teeth indeed. This was because they rarely ate sugar. Before the 16th century, sugar was an expensive luxury that few Westerners could afford. Thanks to this lack of sugar, most people’s teeth lasted a lifetime. Therefore, most of our ancestors got by just fine with only one set of adult teeth.
Nowadays however, we all eat diets high in sugar. While sugar tastes great, it has the unfortunate side-effect of encouraging plaque, cavities and gum disease. Ideally, we would simply evolve to grow new sets of teeth, like sharks or elephants. However, evolution is a very slow process. This means we’re all stuck with just one set of adult teeth for now.
Imagine a future technology where dentists could stimulate the growth of new teeth. If you get tooth decay today, it would be no problem – you would just get new teeth tomorrow! There would be no need for dentures, implants and crowns, because a dentist could just grow a new tooth for you instead.
In fact, scientists are already working on this kind of technology. Researchers at Harvard university have managed to grow new teeth in rats. The technology involves shining a laser to activate stem cells, which are cells that can grow into any type of cell in the body, including teeth.
Unfortunately however, it probably will be decades before this kind of technology is commonplace in dental clinics. Until then, you only have one option: maintain a good oral hygiene routine, including brushing, flossing and mouthwash. And don’t forget to see a dentist regularly!