Best known as a surgical inconvenience, wisdom teeth are actually a third set of molars, which helped our ancestors munch on rough food like roots, nuts, and meat, especially when other teeth fell out. About 35 percent of people never develop wisdom teeth, but the rest begin developing them around age 10, and the grinders erupt in the mouth between ages 17 and 25. This age bracket gives the molars their name: It refers to the time when young adults become wiser (ostensibly). Though fully-grown or healthy wisdom teeth may not need to be removed, if left in place they may cause gum disease, cysts, or damage to nearby teeth. According to a 2007 study published in the
American Journal of Public Health, 10 million wisdom teeth are extracted from about 5 million people in the United States each year.
