Clever little teeth! Part 1, the miracle of renewal!

• January 18, 2012
• Dr. Catherine-Anne Walsh

Hello, we’re back and wishing you all a Happy New Year! I love this time of the year: everyone feeling positive and ready to move on from the year before, vowing to make this one better than last! Riding that wave of positivity, in this series, we will go through only a few of the many amazing things teeth do or help us do.  I hope it reminds you teeth are not just a nuisance and a reason to go see a dentist, they’re also one of nature’s little miracles.

The miracle of renewal

In our lifetime, we are given two sets of teeth, one which lasts us for our early childhood (six months to 11 years of age) and another, more durable and complex, which lasts us for the rest of our lives. It’s nature’s way of adapting to our growth and our changing function as we grow.

Our baby teeth know when to go!

Even if we did nothing to help, our baby teeth would fall out on their own. And it’s not the adult teeth ‘pushing’ them out. The phenomenon of tooth exfoliation (loss of baby teeth) and tooth eruption (teeth coming through) is very controversial amongst researchers of oral biology, but it seems to be a sort of pre-programmed process which takes place only if all the factors involved come together just at the right time. The baby teeth slowly start to lose their root lengths (the roots resorb or dissolve) while at the same time the adult teeth underneath slowly grow up towards the surface, moving, but also growing their roots at the same time. This wonderful mysterious process is not 100% fail-proof. It can also go wrong, some teeth do not erupt and become impacted (stuck). Some baby teeth ‘forget’ to fall out. It is important to protect children’s teeth during sports activities with a child mouthguard to help prevent injury and ensure healthy teeth.

Our new adult teeth can also grow other things

The root tip of an adult tooth continues to develop for a few years after the tooth crown is visible in the mouth. During this time, there are some amazing, pluripotent stem cells hovering around the tips of the roots, building blood vessels, nerves, dentine, cementum, ligament, and whatever the tooth needs to complete its form and function. Sometimes, these young teeth can be accidentally avulsed (knocked out). When that happens, they are usually put straight back into the socket. Previously, after such a traumatic event, the tooth would inevitably lose its blood supply and innervation and “die”, but very often its root would also be replaced by bone, leading to the loss of a tooth. Nowadays, dentists can ‘agitate’ the stem cells around the tooth and provoke them to keep producing the missing parts of the tooth after the tooth has been placed back into its socket. If the young tooth is not needed in the mouth, e.g if a wisdom tooth is removed, the stem cells around the root tip can be harvested for use all around the body.

And if that’s not cool enough:

Well, if the above miracle does not sound ‘miraculous’ enough for you, you may know or have heard of people being able to open beer bottles with their teeth. If you ever see someone do it…

Give them my details!