Wisdom teeth

Long after our primary (baby) teeth have been replaced by permanent teeth, we get our third molars - a set of four permanent teeth which come in behind the upper and lower 12-year-molars. Third molars are called "wisdom" teeth because they generally erupt between 17 and 21 years of age, when we reach adulthood.

Why do wisdom teeth cause problems?

Wisdom teeth that are healthy and properly positioned can be a valuable asset to the mouth. Unfortunately, this is often not the case, and problems develop that require their removal. For example, when the jaw is not large enough to accommodate these teeth, they can become impacted - unable to come in or move into their proper place. They may grow sideways, emerge only partway from the gum, or remain trapped beneath the gum and bone. Impaction occurs most often in the third molars of the lower jaw. After examining your mouth and taking X-rays, your doctor will discuss whether your wisdom teeth should be removed.

Why are wisdom teeth removed?

Extraction of third molars can protect the overall health of the mouth. It is generally recommended when the following conditions occur:

• Wisdom teeth only partially erupt. This leaves an opening for bacteria to enter around the tooth and cause an infection. Pain, swelling, jaw stiffness and general illness can result.
• Impacted wisdom teeth may continue growing without enough room, damaging adjacent teeth. This continued pressure can eventually destroy the healthy second molar tooth.
• A fluid-filled sac (cyst) or tumor forms, destroying surrounding structures such as bone or tooth-roots.