Chapter 177. Dental Abscess Incision and Drainage

Patients frequently present to the Emergency Department complaining of a “toothache”. The common causes of toothache pain are multiple.1 Similarly, there are multiple etiologies for a dental abscess (Table 177-1). Distinguishing the type of dental abscess can have an impact upon treatment decisions, prognosis, and patient morbidity.2–5 The accurate diagnosis and proper treatment of these maladies require that the Emergency Physician has a basic understanding of dental anatomy, pathophysiology, and simple dental treatment protocols. Many of these conditions can be managed initially through the Emergency Department. The prudent Emergency Physician must have a clear understanding that these infections can rapidly become complicated and may require timely consultation or referral.

Teeth are essentially composed of three layers (Figure 177-1). These layers, from the outside working inward, are the enamel, the dentin, and the pulp. The dentin and pulp are living tissues that are sensitive to noxious stimuli. The crown is covered with enamel, while the root is covered with a substance known as cementum. Cementum helps attach the tooth to the surrounding alveolar bone via the periodontal ligament (PDL). The neurovascular supply enters the pulp through the apical foramen at the root apex. The pulp contains only pain transmitting neuronal fibers, while the PDL contains both pain-sensitive and pressure-sensitive fibers.7 Dental abscesses arise when bacteria penetrate the normal anatomic and physiologic barriers of the tooth and surrounding structures. This can lead to a localized collection of purulence contained within the tooth (pulpal abscess), or around the apex of the tooth (periapical abscess) (Figure 177-2). Alternatively a dental abscess may localize to the supporting structures of the tooth (periodontal abscess) or strictly to the adjacent soft tissues (pericoronitis) (Figure 177-2).

Pulpal or Periapical Abscesses

Dental abscesses often arise from pulpal necrosis secondary to dental caries or a defective restoration.1,3,4,6,7 Dental caries is commonly known as dental decay or “cavities”. This is the direct destruction of the tooth substance by the acidic bacterial products of normal oral flora. A carious tooth may not initially be painful. The products of inflammation eventually reach the dental pulp as the disease process progresses and the tooth will become sensitive.1–3,7–9 This is known as pulpitis. Patients will report nonlocalizable and intermittent symptoms. This process may initially be reversible by routine dental treatment (e.g., a filling), but the pulp will rapidly necrose and die if it becomes infected. If the infectious process is allowed to continue, products from the necrotic pulp may escape the confines of the tooth via the apical foramen and begin to involve the PDL and surrounding alveolar bone. This is known as a periapical abscess, and makes the infected tooth easily localizable by patient complaints of spontaneous or constant sensitivity, and/or tenderness to gentle percussion.1–3,5–7,9 The infection could likely be halted at this stage of the pathophysiologic process with a “root canal,” which is essentially an incision and drainage procedure performed on the inside of a tooth by an Endodontist.6,7

If left unchecked, however, the bacterial products of a periapical infection and the host's immune response to it can lead to a progressive destruction of the dental supporting tissues, including the alveolar bone. At this point the tooth will become increasingly mobile. The infection will follow the path of least resistance as it penetrates through the alveolar bone into the surrounding soft tissues.6,7 It may perforate laterally to form a vestibular abscess (Figure 177-3A). Alternatively, it may perforate medially to form a palatal or lingual abscess (Figure 177-3B). Further spread will be dictated by the proximity of the muscle attachments and fascial planes.3,5–7,9–11 The appropriate treatment for an abscessed tooth depends on the extent of infection. It may include endodontic treatment, incision and drainage, extraction, or a combination of these.6,7 An incision and drainage procedure is warranted if the infectious process extends outside the alveolar bone and involves the soft tissues.5,6,7,9,10

The extension of infectious products outside the root apex can lead to a multitude of clinical signs throughout the head and neck. Swelling, erythema, warmth, fluctuance, and spontaneous drainage of purulence via a sinus tract or fistula may be seen intraorally or extraorally. A localized or generalized cellulitis may be present. There is often a foul breath odor.1,5,6,10 One or more of the numerous named fascial spaces of the head and neck may become involved via direct extension.3,5–8,10–16 Systemic symptoms may become involved including fever, malaise, anorexia, and leukocytosis.5,6,8,10,12 Structures immediately adjacent to the oral cavity may become involved. This can result in trismus, reactive sinusitis, lymphadenopathy, osteomyelitis, cavernous sinus thrombosis, airway compromise, and/or a brain abscess.3,11–16

Dental infections extending into any of the fascial compartments of the head and neck are dangerous, can rapidly progress, and are considered complicated infections.3,5–7,10,12–16 Patients typically have a toxic appearance with systemic signs and symptoms. They often present with dysphagia, dysphonia, or dyspnea. The classic example is Ludwig's angina or a concurrent bilateral involvement of the sublingual, submental, and submandibular spaces. This represents an immediate threat to the airway.11,13,15,16 Infectious extensions into the lateral pharyngeal, retropharyngeal, and prevertebral spaces are rare and can lead to disastrous complications such as aspiration, mediastinitis, and airway compromise. A retropharyngeal space measuring greater than 3 to 5 mm on lateral soft tissue neck radiographs or CT scans is indicative of airway compromise.10 Consider rapid and aggressive management with prompt surgical consultation, broad-spectrum antibiotics, and early airway intervention in patients who are suspected of manifesting any of these processes.3,8,10–15

Periodontal Abscesses

Poor dental hygiene and poor nutrition lead to local inflammation of the tissues surrounding and attaching the tooth to its socket, allowing bacterial penetration. Early periodontal disease is isolated to the gingiva and known as gingivitis.5,17 Alveolar bone may be destroyed as the disease progresses, leading to gingival pockets and tooth mobility.1,5,18 Food debris or plaque may become trapped within these pockets and create a localized infection known as a periodontal abscess.4,5,17 Periodontal disease is very common in pregnant women.

Patients may complain of bleeding, foul odor, bad taste, loose teeth, pain, or swelling. The physical examination reveals gingival tissue that may be erythematous or necrotic and bleed easily. Heavy accretions of dental plaque and calculous may be present. An abscess may present as a focal swelling, tooth mobility, pain on percussion, and purulence that is expressible from the gingival sulcus.1,5,17,18 It may be impossible, with current dental caries, to differentiate a periapical abscess from a periodontal abscess without radiographs.3,5 In fact, both lesions may occur together.18 A periodontally diseased tooth may be so mobile that it cannot be salvaged and requires extraction.5

True periodontal abscesses rarely spread beyond the local dentoalveolar structure and rarely require an urgent referral.3,4 Treat an isolated periodontal abscess with dental anesthesia, incision and drainage, and dilute peroxide (1:5 solution or 5%) or chlorhexidine rinses. Prescribe oral antibiotics for evidence of spread, if there is a delay to definitive care, or for systemic manifestations.1,3–5,18 Appropriate antibiotics include penicillin, clindamycin, or erythromycin. Refer patients with these lesions to a Dentist within 24 to 48 hours for definitive follow-up care to avoid recurrence.1,3,5

Pericoronitis

Inflammation can occur around the crown of any erupting tooth and is common around impacted teeth, especially the third molars.1,3,4,19 This condition is known as pericoronitis. It is often exacerbated by the impaction of food under the soft tissue. Progression of the primary process or overzealous treatment can easily lead to extension of the infection posteriorly to multiple contiguous spaces, including the retropharyngeal space.1,3,19,20 Simple cases are easily managed in the Emergency Department. Always maintain a very low threshold for consultation and referral of patients with complicated presentations.

Treatment of pericoronitis may include dental anesthesia, direct saline irrigation, warm saltwater rinses, dilute peroxide or chlorhexidine rinses, and oral analgesics. The presence of swelling, trismus, and inflammation may be severe enough to warrant a course of oral antibiotics.1 Some authors advocate antibiotic coverage in essentially all cases.1,10,19,21 Definitive treatment requires the completed eruption or extraction of the tooth. Refer the patient to a Dentist or Oral Surgeon for follow-up and definitive care within 24 to 48 hours.

The indications for dental abscess incision and drainage include a periapical or periodontal abscess with clinical evidence of alveolar penetration and soft tissue spread.9,10 Some authors recommend incision and drainage for purely cellulitic processes.4,5,11 Extraoral incision and drainage is indicated only for dental infections progressing toward inevitable spontaneous extraoral drainage.3,10 Drain all other dental abscesses intraorally.

A review of the current literature reveals no direct contraindications to the incision and drainage of a dental abscess. Maintain a low threshold for consultation and referral to a surgical specialist for any patient with rapidly progressing infections, difficulty breathing, difficulty swallowing, fascial space involvement, temperature greater than 101 °F (38.3 °C), white blood cell count greater than 10,000, severe trismus (manifested by mandibular opening less than 10 mm or inability to adequately visualize the hypopharynx), a toxic appearance, compromised host defenses, or who are children.3,6,10,22

• #15 scalpel blade on a handle
• #11 scalpel blade on a handle
• Povidine iodine or chlorhexidine solution
• Minnesota retractor
• Wieder tongue retractor
• Frazier suction catheter
• Suction source and tubing
• Needle driver
• Hemostat
• Suture, 4-0 and 5-0 silk
• Gelfoam
• 0.25 inch wide Penrose drain
• Light source, overhead or headlamp

Explain the procedure, its risks, and benefits to the patient and/or their representative. Obtain dental radiographs if the infection is from a dental source.5,6,10 Obtain an informed consent for the procedure. Provide adequate anesthesia; ideally in the form of a dental block. Obtain a separate informed consent for the dental block. Direct infiltration into the area of purulence does not achieve adequate anesthesia and risks spreading the infection by inoculation.3,5 Dental blocks may require augmentation with direct infiltration anterior and posterior to the abscess. Anesthetize the areas adjacent to the abscess last to avoid seeding. Refer to Chapter 176 for a complete discussion of dental analgesia and anesthesia. The application of procedural sedation may be required if adequate local anesthesia is not possible.10 Refer to Chapter 129 for the complete details regarding procedural sedation and analgesia.

Prophylaxis to prevent infective bacterial endocarditis should be addressed in the appropriate patients prior to incision and drainage of a dental abscess in accordance with the policy put forth by the American Dental Association. Further information and specific antibiotic regimens can readily be found at the website of either the American Heart Association or the American Dental Association (Table 177-2).23,24

Simple Intraoral Incision and Drainage

There are two techniques for intraoral incision and drainage. The first technique is to make a simple stab incision with a #11 scalpel blade in the area of greatest fluctuance and in the area that best facilitates dependent drainage (Figure 177-4A). Do not make the incision more than 1 cm in length. Gently insert a closed, curved hemostat into the incision (Figure 177-4B). Gently spread the jaws of the hemostat in several different directions to break up any loculations (Figure 177-4C). Express and suction any remaining purulence. Insert a sterile rubber drain cut from a 0.25 inch wide Penrose drain or from a sterile surgical glove (Figure 177-4D). Place one to two silk sutures through the drain and the oral soft tissues. This will ensure that the drain does not fall out and result in premature closure of the incision or aspiration of the drain.

The second technique for simple intraoral incision and drainage differs only in the location of the incision. Make an incision with a #15 scalpel blade at the alveolar crest within the gingival sulcus, scalloping around the teeth. Extend the incision one tooth medial and distal to the tooth in question or the area of the abscess. Gently elevate the attached gingiva from the bone with a blunt instrument. Continue the blunt dissection until the abscess cavity is penetrated. This typically occurs just within the level of unattached gingiva. The remainder of the procedure is as described above. This technique affords some mechanical advantages to the operator and is well tolerated by the patient postoperatively. It can be performed in both arches, buccally, palatally, and lingually. It is often useful for draining a periodontal abscess.

Extraoral Incision and Drainage

Extraoral incision and drainage is indicated when a dental infection appears to be progressing toward inevitable spontaneous extraoral drainage.10 This procedure requires more attention and skill because of the numerous underlying vital structures and the possible cosmetic consequences.3,10 Make every effort to avoid extraoral incision and drainage.3 Consider consulting a Dentist or Oral Surgeon before performing an extraoral incision and drainage.

Extraoral incision and drainage differs from the intraoral approach.3,10,11 Advise the patient that they will almost certainly have a visible scar after the incision heals.3,10 Extraoral incision and drainage requires the use of aseptic technique. Prepare the area with povidone iodine or chlorhexidine solution and allow it to dry. Apply sterile drapes to isolate a field. Perform local subcutaneous infiltrative anesthesia of the skin. Use a separate needle and syringe for any intraoral anesthetic techniques.

Make a 1.0 to 1.5 cm long incision with a #15 scalpel blade in an area of healthy skin, proximal to the site of expected breakdown and in a location that facilitates dependent drainage (Figure 177-5). Extend the incision into the subcutaneous tissues. This is another critical difference from the intraoral technique. Insert a hemostat to penetrate and drain the abscess cavity. Spread the hemostat in several directions to break up any loculations. The remainder of the procedure is performed as described as above. Scarring with extraoral incisions is virtually universal.

Facial infections in children tend to develop and progress more rapidly. They are more likely to present with systemic signs and symptoms.25 Facial infections in children are also more likely to be associated with complications, such as dehydration or bacteremia.25 Unlike adults, the anatomic location of a facial infection in a child can be a more useful guide in determining its source and management.25 In general, upper face infections tend to be more common in children less than 5 years of age and frequently have no identifiable source. Children older than 5 years of age more commonly have lower face infections and typically have an odontogenic or wound-related source.25 According to the American Academy of Pediatric Dentistry, a child presenting with a facial swelling secondary to a dental infection should receive immediate dental attention.26 Lastly, in sharp contrast to adults, children with facial infections in either location more frequently respond to antibiotics alone and may not require an incision and drainage procedure.25

Basic postoperative assessment includes inspecting the operative site for the minor complications described below. Assess adequate drain retention. A loose intraoral drain may represent an aspiration risk. Observe the patient for postprocedural bleeding. It can be controlled with the application of pressure, injection of a local anesthetic agent containing epinephrine, or topical Gelfoam. Wound cultures are not indicated unless the patient is immunocompromised or the infection is recurrent. The wound cultures usually demonstrate mixed oral flora with no predominate organism.

The application of warm moist compresses, oral fluids, rest, and good nutrition are mainstays in the treatment of any inflammatory process. Patients may benefit from a soft, bland diet and frequent oral rinses with a warm saltwater solution. All patients require postoperative oral analgesics.3,5,10,11 Patients with an extraoral incision require dressing changes.3,5,10,11 Provide the patient with adequate supplies and teaching. Instruct the patient on the application of pressure if postprocedural bleeding occurs.

The use of antibiotics in light of adequate drainage is somewhat controversial. Clear-cut indications for oral antibiotics in orofacial infections include cellulitis, extraoral incision, systemic symptoms, persistent infection, pericoronitis, fascial space involvement, and immunocompromised patients.4,7,10,16 The prudent Emergency Physician is advised to err on the side of caution while the academics quarrel over antibiotic indications. Penicillin is the drug of choice for the empiric treatment of dental-related infections. Alternatives to penicillin include erythromycin, clindamycin, or a cephalosporin. Clindamycin is the first alternate choice. It is especially useful when anaerobes are suspected or in recalcitrant infections where sensitivities are lacking.3,5,6,10

Allow the intraoral drain to remain in place until the swelling has resolved and purulent drainage has ceased. Evaluate the patient for drain removal or advancement in 24 to 48 hours. Prescribe oral antibiotics and analgesics during this time. Refer the patient to a Dentist within 24 hours.

Minor postoperative pain, swelling, bleeding, drainage, and possibly bruising can be expected following the incision and drainage of a dental abscess. Significant postprocedural bleeding can be controlled with pressure, a vasoconstricting local anesthetic agent, or topical Gelfoam.5,6,17,18 An incision and drainage tract that communicates freely between the oral cavity and the external face represents a significant complication. Refer these patients to a Plastic or Oral Surgeon.

The recognition of common dental-related infections such as pericoronitis, periodontal abscesses, and dental abscesses can impact patient prognosis and morbidity. The diagnosis and treatment of these maladies, and their complications, requires knowledge of dental anatomy and pathophysiology. The Emergency Department management of these infections is quick and simple. Refer all patients to a Dentist or Oral Surgeon for definitive care of their teeth.