Impacted teeth usually occur because of crowding or lack of space in the bone. Third molars (wisdom teeth), particularly the lowers, are the last to erupt and are more likely to be impacted. Because of crowding and difficulty with cleaning, decay in adjacent teeth, as well as gum disease often occurs. Surgical removal of impacted teeth is often recommended, but may be optional unless the dentist recommends. The surgery is usually a minor painless procedure and can be done using local or general anesthesia. If the impacted tooth is not removed, it may lead to gum diseases, decay and bad breath, damage to the adjacent teeth and may cause cyst.