By this point in life, you’ve probably realized that your teeth are pretty tough. Otherwise, we’d all break them into tiny shards every time we crunch on a stray popcorn kernel or accidentally bite down on a utensil. But if you’ve ever suffered any kind of chipped or broken tooth, you know your pearly whites aren’t invincible. Just how strong are teeth? Let’s look to the facts to find out.
Mohs Hardness Scale Rating
Your teeth are mostly composed of hydroxyapatite, a form of calcium phosphate. If that sounds like a mouthful (pun intended), all you really need to know is that the apatite group of minerals are a 5 on the Mohs hardness scale. The scale goes from 1 to 10, with 1 being the softest kind of material (talc) and 10 being the hardest (diamond).
The fact that your teeth fall in the middle of the scale proves just how tough they are. With a score of 5, teeth are harder than steel (4-4.5), iron (4.5), and nickel (4).
Understanding Why Teeth Are Brittle
Before you go chomping down on steel to test out the strength of your teeth, consider that hardness does not equal resistance to impact. Sure, you won’t be able to scratch your teeth on steel. However, because human teeth are brittle, chomping down can cause them to chip.
New research into tooth strength has revealed that your teeth are made of a basket-weave structure that gives them superior strength when pressure is applied. For example, if an impact does cause a crack to start forming, the weaving microstructure will prevent the crack from spreading and tearing through all of the enamel.
Measuring the Toughness of Teeth
Your jaw is a powerful tool and can exert a force of 168 pounds in a single bite. This equates to a bite pressure of 5600 pounds per square inch, which sounds like it should be catastrophic to your teeth. However, teeth can resist up to 30,000 pounds of compressive force. If that sounds like a lot, that’s because it is. So with the ability to handle that type of force, how do cracks ever even happen?
You’ve got to keep in mind that cracks can form over time. The basket-weave structure mentioned above does do a good job of keeping cracks from spreading in a single impact. However, with repeated impacts over time, this crack will spread. By the time your tooth actually breaks, it might just need a slight tap to shatter. This is what often gives the appearance of teeth being weak. Only a 1/100th of an inch crack is necessary to cause tooth failure.
Causes of Chipped Teeth
Now that you know all about the strength of teeth, here are a few things to avoid to prevent any chips or cracks from forming in the future.
- Chewing on ice or hard objects
- Using your teeth to open bottles or cut through something
- Grinding or clenching your teeth
- Forgetting a mouth guard when playing sports
- Getting a metal tongue piercing
Keep in mind that if you do suffer a chipped tooth, we are here to help. Schedule an appointment today to learn more about getting a filling, crown, or implant to brighten your smile.