A dental abscess is an infection within the tooth, bone or tissue supporting a tooth. Abscess' can have symptoms ranging from mild to severe pain. They often present as a "pimple" on the gum tissue that comes and goes. They are generally caused by deep decay, tooth fracture or severe periodontal disease. Once a tooth has developed an abscess it will require either root canal treatment or extraction. Symptoms of an abscess can be alleviated by antibiotics but until the tooth is properly treated the infection and symptoms will reoccur.