What Is a Wisdom Tooth?

From babyhood to adolescence, teeth erupt in stages: first incisors, then canines, premolars and molars and, finally, wisdom teeth. The latter is often the most intriguing; what is a wisdom tooth? Dentists call them third molars, and they appear at the back of the mouth. Some people don't experience a single problem with their wisdom teeth, but in others, they can cause pain, infection and other instances of discomfort.

Where and When Wisdom Teeth Come In

People usually develop four wisdom teeth, each emerging behind the molars on both sides of the upper and lower jaw. According to the American Dental Association (ADA) Mouth Healthy site, they usually appear between the ages of 17 and 21. How they emerge differs with the individual. Nonetheless, Fred Quarnstrom, DDS from the American Dental Board of Anesthesiology, explains wisdom teeth may only partially erupt, or even stay buried within the gum tissue. Teeth that don't appear and remain covered by this tissue or bone are called "impacted."

Why They Come In

Because wisdom teeth cause so many problems and are not really needed for chewing, doctors speculate about their function. Wisdom teeth begin growing in the jaw around the age of seven, and not just before or at birth like other teeth, says Kamal Busaidy, BDS, FDSRCS of The University of Texas Health Science Center at Houston. Throughout most of human history, the typical diet was abrasive to teeth. Under the circumstances, wisdom teeth may have been useful in the past for replacing molars that had become worn out. Now that diets are softer, teeth don't do this as quickly, and there are no gaps for wisdom teeth to fill. Dr. Quarnstrom states there is also some evidence modern jaws are smaller than those of prehistoric humans.

What Happens

Problems with wisdom teeth primarily include pain and discomfort, infections, gum disease and tooth decay. Some of these are due to the difficulty brushing so far back in the mouth. Brushing with a slim, long-handled toothbrush such as Colgate® Slim Soft can help to prevent these problems. Other serious effects of impacted wisdom teeth occur when cysts form below the teeth. These cysts can cause loss of bone in the jaw, and put pressure on the jaw's nerves.

Problems with wisdom teeth usually end with their removal. Dentists often prefer to remove wisdom teeth when patients are in their late teens or early 20s, before they cause problems. At this age, wisdom teeth's roots have not solidified in the jaw bone, and are easier to remove than in older patients. Removing wisdom teeth later in life also carries a slightly higher risk of damage to a major nerve in the jaw, called the inferior alveolar nerve. Younger patients often recover from sedation faster, as well.

Adolescents wearing braces or other orthodontic appliances, according to Busaidy, often have their wisdom teeth removed at the end of their treatment. This is because emerging wisdom teeth can alter tooth alignment after they have been straightened.

So, what is a wisdom tooth? It has nothing to do with growing wiser – only growing older. If your wisdom teeth give you pain or discomfort, see your dentist. Early treatment greatly reduces your risk of bigger problems later.

If you've had or need to have your wisdom teeth extracted, find out more about wisdom teeth recovery in the Colgate Oral Care Resources.

Are you practicing good oral hygiene after surgery?

If you’ve recently had your wisdom teeth removed, it’s important to keep your mouth clean even after your mouth heals. Try one of our germ fighting products for a healthy mouth.