It’s pretty easy to damage one’s teeth. Anyone who chooses not to practice oral hygiene will get a set of decayed teeth in a very short time. Or one simply has to figure in enough rough play to have one or two chipped. If teeth were so tough, nobody would be visiting a cosmetic dentistry practice anywhere to have their damaged teeth fixed. But that’s not the entire — and exact — story.
A Smile Tough-As-Nails
Believe it or not, teeth are tough, but not in a ‘conventional’ way. One look at the composition of a tooth holds the answer. As almost everyone will know, the hard outer layer is called the enamel. It acts as a sort of armour for the more delicate insides of a tooth, which include the extremely sensitive nerves. If not for the enamel, no one will be able to eat any food (especially hot, cold, or spicy ones) due to the nerves being exposed.
How hard is the enamel? For a comparison, it’s harder than human bone. Teeth enamel is practically the hardest substance in the human body. Its hardness and the protection it gives is further accentuated by the dentin, another layer of hard substance under the enamel. Relatively, dentin is as hard as human bones, but not as hard as enamel.
Enamel’s hardness is also well-documented. According to the Mohs Scale of Hardness (which diamonds top with a 10 out of 10), teeth enamel scores a 5 out of 10. This makes them the hardest biological material. But the thing is, ‘hardness’ is not a measure of how indestructible something is, but rather how resistant it is to scratch. A tooth’s hardness means it can’t be scratched easily (even steel is much easier to scratch), but it’s not necessarily durable. As a result, it’s very brittle compared to other materials.
Another comparison further cements the toughness of a human smile. After comparing the microscopic structures of human and shark teeth, scientists confirm that the two are equally strong. Researchers from the University of Duisburg-Essen in Germany found that human teeth are made up of crystals in a special arrangement, which is ‘glued’ together by proteins that stop cracks from covering the entire tooth. This structure means that human teeth are as strong as that of the tiger shark, which is among the deadliest of the shark species.
It seems like human teeth are indeed tough-as-nails, if not as deadly as that of an apex ocean predator.