An abscess is a localized, usually painful swelling that occurs when the body’s white blood cells attack and isolate an infection, forming pus. Abscesses can be caused by bacteria, parasites and foreign objects.
Dentists commonly see two types of abscess, dental and periodontal. A dental abscess occurs when the dental pulp deteriorates and forms fluid under pressure, usually in response to an invasion of bacteria from tooth decay. The pressure causes pain in the bone around the roots of the tooth and sometimes results in swelling of the soft tissue near the tooth. While an abscessed tooth may be temporarily helped by taking antibiotics, the only definite treatments are endodontic (root canal) treatment or extraction of the tooth followed by prosthetic replacement.
A periodontal abscess does not originate from the dental pulp inside the tooth, but rather occurs when bacterial plaque or a foreign object causes a rapidly growing infection in the periodontal pocket around the tooth. The result is a painful swelling that usually occurs on the gingival (gum) tissue. If left untreated, a periodontal abscess destroys the bone and supporting ligaments of the tooth, resulting in tooth loss. Treatment for a periodontal abscess usually involves draining the infection, thoroughly scaling (cleaning) the root surface of the tooth and, in many cases, taking an antibiotic.