A wisdom tooth, in humans, is any of the usual four third molars. Wisdom teeth usually appear between the ages of 17 and 25. Most adults have four wisdom teeth, but it is possible to have fewer (hypodontia), or more, in which case they are called supernumerary teeth. Wisdom teeth commonly affect other teeth as they develop, becoming impacted or "coming in sideways." They are often extracted when this occurs. Dr. Hicks will advise extraction of wisdom teeth following a dental exam and a panoramic x-ray, but only if needed.