Most people develop 32 teeth by the time they reach 18 years of age. However, the average mouth is only big enough for 28 teeth. The last 4 teeth to erupt are the wisdom teeth, usually coming in during the late teens and early twenties. Wisdom teeth frequently become stuck as they try to erupt, remaining partially under the gum tissue. When a wisdom tooth fails to erupt normally it is termed “impacted.” Impacted wisdom teeth may cause problems in the future such as infection, periodontal disease, cysts, and crowding.
Infection:
Impacted wisdom teeth create an excellent environment for bacteria to thrive. Because wisdom teeth are so difficult to keep clean, bacteria tend to multiply around them and cause infections and cavities. The best time to remove wisdom teeth is in the teens to early twenties, before they begin causing these problems.
Periodontal Disease:
Also known as gum disease, periodontal disease is frequently seen around wisdom teeth. This is because they are difficult to clean given their position in the back of the mouth. Periodontal disease is a slowly progressive, chronic condition by which the bone supporting the tooth is lost. When present around a wisdom tooth, periodontal disease often affects the molar in front of the wisdom tooth. Additionally, the wisdom tooth can serve as a reservoir of bacteria that affect the rest of the mouth.
Cysts:
Although rare, cysts and benign tumors can form around impacted wisdom teeth. These lesions are similar to a water balloon surrounding the wisdom tooth. As they expand they destroy the jaw bone and move other teeth.
Crowding:
Wisdom teeth may contribute to the crowding of front teeth, particularly the lower front teeth. Orthodontists frequently request their patients have wisdom teeth removed prior to taking off braces in order to facilitate orthodontic stability.