Periodontal Abscess

The periodontal abscess is typically found in patients with untreated periodontitis and in association with moderate-to-deep periodontal pockets.5,25 Periodontal abscesses often arise as an acute exacerbation of a preexisting pocket⁶ (Figure 42-1). Primarily related to incomplete calculus removal, periodontal abscesses have been linked to a number of clinical situations.^8,15,16,24 They have been identified in patients after periodontal surgery,¹² after preventive maintenance (Figure 42-2),^7,10,17,21 after receiving systemic antibiotic therapy,²⁶ and as the result of recurrent disease.^15,16 Conditions in which periodontal abscess is not related to inflammatory periodontal disease include tooth perforation or fracture^2,24 (Figure 42-3) and foreign body impaction.^1,23 Poorly controlled diabetes mellitus has been considered a predisposing factor for periodontal abscess formation²² (Figure 42-4). Formation of periodontal abscess has been reported as a major cause of tooth loss^12–21; however, with proper treatment followed by consistent preventive periodontal maintenance, teeth with significant bone loss may be retained for many years⁷ (see Figure 42-10).

Gingival Abscess

The gingival abscess is a localized, acute inflammatory lesion that may arise from a variety of sources, including microbial plaque infection, trauma, and foreign body impaction.²² Clinical features include a red, smooth, sometimes painful, often fluctuant swelling (Figure 42-5).

Pericoronal Abscess

The pericoronal abscess results from inflammation of the soft tissue operculum, which covers a partially erupted tooth. This situation is most often observed around the mandibular third molars. As with the gingival abscess, the inflammatory lesion may be caused by the retention of microbial plaque, food impaction, or trauma.

Acute Versus Chronic Abscess

Abscesses are categorized as acute or chronic. The acute abscess is often an exacerbation of a chronic inflammatory periodontal lesion. Influencing factors include increased number and virulence of bacteria present, combined with lowered tissue resistance and lack of spontaneous drainage.11,25 The drainage may have been prevented by a deep, tortuous pocket morphology, debris, or closely adapted pocket epithelium blocking the pocket orifice. Acute abscesses are characterized by painful, red, edematous, smooth, and ovoid swelling of the gingival tissues.^15,16,25 Exudate may be expressed with gentle pressure; the tooth may be percussion sensitive and feel elevated in the socket (Figure 42-6). Fever and regional lymphadenopathy are occasional findings.²²

The chronic abscess forms after the spreading infection has been controlled by spontaneous drainage, host response, or therapy. Once homeostasis between the host and infection has been reached, the patient may have few or no symptoms.⁹ However, dull pain may be associated with the clinical findings of a periodontal pocket, inflammation, and a fistulous tract.²²

Box 42-1 compares the signs and symptoms of the acute and chronic abscess.

Periodontal Versus Pulpal Abscess

To determine the cause of an abscess and thus establish a proper treatment plan, it is often necessary to perform a differential diagnosis between a periodontal and pulpal abscess⁴ (Box 42-2 and Figures 42-7 and 42-8).