When disc brakes for high performance cars arrived on the scene we began to hear of warped brake discs on road going cars, with the same analyses and diagnoses. Typically, the discs are resurfaced to cure the problem and, equally typically, after a relatively short time the roughness or vibration comes back.
As a result, the cheek teeth, like the incisors, have evolved to continuously grow throughout life. In other rodents, the diet of tubers, seeds, and grain requires little chewing, resulting in little wear of the cheek teeth.
Kids have about 20 teeth by the time they turn 3 years old. This first set of teeth are called milk teeth, baby teeth or primary teeth. By the time you are five or six, your first permanent teeth will start coming in. The permanent teeth lie just beneath the roots of the baby teeth.