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 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).

Figure 42-1 A, Deep furcation invasions are a common location for the periodontal abscess. B, Furcation anatomy often prevents the definitive removal of calculus and microbial plaque.

Figure 42-2 Postprophylaxis periodontal abscess resulting from partial healing of a periodontal pocket over residual calculus.

Figure 42-3 A, Fistula is observed in attached gingiva of maxillary right canine. B, Elevated flap shows the cause to be a root fracture.

Figure 42-4 Localized periodontal abscess of mandibular right canine of male adult with poorly controlled type 2 diabetes mellitus. For some patients, periodontal abscess formation may be the first sign of the disease.

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).

Figure 42-5 Plaque-associated gingival abscess of mandibular right canine.

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

Figure 42-6 Patient presenting with acute abscess complained of dull pain and a sensation of tooth elevation in the socket. Signs of tissue distention and exudation are evident.

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).

Figure 42-7 A, Maxillary right first molar with fistula on the attached gingiva. B, Using local anesthesia, periodontal probe is introduced through the fistula and angled toward the root end. C, Surgical flap elevation demonstrates failed endodontic therapy and tooth fracture as causing the fistula.

Figure 42-8 A, Periodontal abscess of maxillary left first molar. B, Periodontal probe is used to retract the pocket wall gently.

Acute Abscess

The acute abscess is treated to alleviate symptoms, control the spread of infection, and establish drainage.¹⁹ Before treatment, the patient’s medical history, dental history, and systemic condition are reviewed and evaluated to assist in the diagnosis and to determine the need for systemic antibiotics³ (Boxes 42-4 and 42-5).

Drainage through Periodontal Pocket

The peripheral area around the abscess is anesthetized with sufficient topical and local anesthetic to ensure comfort. The pocket wall is gently retracted with a periodontal probe or curette in an attempt to initiate drainage through the pocket entrance (see Figure 42-8). Gentle digital pressure and irrigation may be used to express exudates and clear the pocket (Figure 42-9). If the lesion is small and access uncomplicated, debridement in the form of scaling and root planing may be undertaken.

Figure 42-9 Gentle digital pressure may be sufficient to express purulent discharge.

If the lesion is large and drainage cannot be established, root debridement by scaling and root planing or surgical access should be delayed until the major clinical signs have abated.¹⁸ In these patients, use of adjunctive systemic antibiotics^13-16 with short-term high-dose regimens is recommended²⁰ (see Box 42-5). Antibiotic therapy alone without subsequent drainage and subgingival scaling is contraindicated.¹⁴

Chronic Abscess

As with a periodontal pocket, the chronic abscess is usually treated with scaling and root planing or surgical therapy. Surgical treatment is suggested when deep vertical or furcation defects are encountered that are beyond the therapeutic capabilities of nonsurgical instrumentation (Figure 42-10). The patient should be advised of the possible postoperative sequelae usually associated with periodontal nonsurgical and surgical procedures. As with the acute abscess, antibiotic therapy may be indicated.²⁵

Figure 42-10 A, Chronic periodontal abscess of maxillary right canine. B, Using local anesthesia, periodontal probe is inserted to determine severity of the lesion. C, Using mesial and distal vertical incisions, a full-thickness flap is elevated, exposing severe bone dehiscence, a subgingival restoration, and root calculus. D, Root surface has been planed free of calculus and the restoration smoothed. E, Full-thickness flap has been replaced to its original position and sutured with absorbable sutures. F, At 3 months, gingival tissues are pink, firm, and well adapted to the tooth, with minimal periodontal probing depth.

Gingival Abscess

Treatment of the gingival abscess is aimed at reversal of the acute phase and when applicable, immediate removal of the cause. To ensure procedural comfort, topical or local anesthesia by infiltration is administered. When possible, scaling and root planing are completed to establish drainage and remove microbial deposits. In more acute situations the fluctuant area is incised with a #15 scalpel blade, and exudate may be expressed by gentle digital pressure. Any foreign material (e.g., dental floss, impression material) is removed. The area is irrigated with warm water and covered with moist gauze under light pressure.

Once bleeding has stopped, the patient is dismissed with instructions to rinse with warm salt water every 2 hours for the remainder of the day. After 24 hours the area is reassessed, and if resolution is sufficient, scaling not previously completed is undertaken. If the residual lesion is large or poorly accessible, surgical access may be required.

Pericoronal Abscess

As with the other abscesses of the periodontium, the treatment of the pericoronal abscess is aimed at management of the acute phase, followed by resolution of the chronic condition. The acute pericoronal abscess is properly anesthetized for comfort, and drainage is established by gently lifting the soft tissue operculum with a periodontal probe or curette. If the underlying debris is easily accessible, it may be removed, followed by gentle irrigation with sterile saline. If there is regional swelling, lymphadenopathy, or systemic signs, systemic antibiotics may be prescribed.

The patient is dismissed with instructions to rinse with warm salt water every 2 hours, and the area is reassessed after 24 hours. If discomfort was one of the original complaints, appropriate analgesics should be employed. Once the acute phase has been controlled, the partially erupted tooth may be definitively treated with either surgical excision of the overlying tissue or removal of the offending tooth.