Pulpitis can progress to necrosis, with bacterial invasion of the alveolar bone, causing an abscess. This is the most common dental abscess in adults, but may occur in children with impaction of a foreign body in the gingiva. Odontogenic infections are polymicrobial, with an average of 4-6 different causative bacteria. Generally, a nonpathologic resident bacterium gains entry when a breach occurs in the host s defenses rather than the introduction of an unusual nontypical microorganism. The predominant species include Bacteroides , Fusobacterium , Peptococcus , Peptostreptococcus , and viridans streptococci.
Mortality is rare and usually is from airway compromise.
Morbidity relates to pain, probable loss of tooth and dehydration. See Complications below. No racial predilection exists. In children, periapical abscess is the most common type of dental abscess. This is due to the combination of poor hygiene, thinner enamel, and the primary dentition having more abundant blood supply which allows for a greater inflammatory response.