Shark Teeth Amaze Researchers with Built-In Toothpaste
As the top predators of the ocean food chain, sharks have developed a myriad of competitive advantages over their rivals. Now, scientists have discovered yet another: super teeth.
Scientists at the University of Duisburg-Essen have discovered that a sharks tooth is made up of fluoride – the active ingredient of most toothpaste. While the surface of a human tooth after brushing might contain at most 1% fluoride, a shark’s tooth in contrast contains 100%.
“In principle, sharks should not suffer from cavities,” explained the study’s co-author Matthias Epple. “As they live in water and as they change their teeth regularly, dental protection should not be a problem for sharks.”
Interestingly, while shark teeth may be superior to ours in terms of health, they are no more harder than our own.
“This finding is surprising, because the mineral fluoroapatite is harder than the mineral hydroxyapatite, so if a tooth were to consist of the mineral alone, a shark tooth would be harder than a human tooth,” Epple said. “It seems as if the human tooth makes up for the less hard mineral by the special arrangement of the enamel crystals and the protein matrix, and ends up being as hard as a shark tooth.”
And don’t forget the other advantage sharks have over our chompers: multiple sets. It’s estimated that some sharks (such as blue shark, catsharks, swellsharks, and sandbar sharks) shed over 35,000 teeth in a lifetime. That’s a lot of tooth fairy dough.