It’s that time of year again – that’s right, SHARK WEEK! Of course, being a dental office, we get a little excited about an entire week dedicated to an animal known and revered for its teeth.
This year’s shark week is particularly exciting for fans of both sharks and teeth because of some recent findings published in the Journal of Structural Biology. Don’t worry, we won’t make you read a scientific journal – all the cool points are summarized below:
Shark teeth naturally contain fluoride.
Yes fluoride, that same ingredient found in most toothpastes, several mouthwashes, and most likely in your drinking water. One of the reasons dentists like fluoride is because of it’s ability to prevent (and in some cases reverse) tooth decay. Because the shark’s teeth are already made of fluoride, they don’t need to use toothpaste and are hereby excused from brushing.
Human teeth are just as hard as shark teeth.
This is actually a surprising discovery. Human and shark teeth both contain dentin and enamel layers. The dentin is the same in each tooth, but the enamel of sharks is made of fluoroapatite (built from fluoride) while human enamel is made of hydroxyapatite (also found in coral reefs). Normally, fluoroapatite is much harder and stronger than hydroxyapatite, but because of the specific arrangement of the crystals that make up human enamel, the strength of the teeth are roughly equal. However, your dentist strongly discourages biting into a live seal.
Sharks don’t get cavities.
Two things are helping sharks. First, the fluoride-based tooth structure is naturally resistant to the acids that cause tooth decay. Second, sharks go through several sets of teeth throughout their life, and most of their teeth don’t stick around long enough to develop a cavity. Which is a good thing, because nobody wants to do fillings on a shark.