Continuing Education Activity

Dental infections, while relatively straightforward regarding diagnosis and access, can be challenging to manage acutely. Dental abscesses or periapical infections typically arise secondary to dental caries (tooth rot related to poor dental hygiene), trauma, or failed dental root canal treatment. Left untreated, these infections can be extremely painful and pose a significant risk of descending into the deep neck space or ascending to intracranial sinuses. Identifying, treating, and educating patients about a dental abscess will grant symptomatic relief and prevent dangerous complications. This activity explains when this condition should be considered for differential diagnosis, articulates how to evaluate this condition properly, and highlights the role of the interprofessional team in caring for patients with this condition.

Objectives:

• Identify the etiologies that can lead to the formation of a dental abscess.
• Assess the examination and evaluation process for dental abscesses, including any necessary diagnostic imaging.
• Evaluate the various antibiotic regimens recommended for treating a dental abscess.
• Explain possible interprofessional team strategies for improving care coordination and communication to advance the evaluation and treatment of dental ascess and improve outcomes.

Introduction

Dental infections, while relatively straightforward regarding diagnosis and access, can be challenging to manage acutely. Dental abscesses or periapical infections typically arise secondary to dental caries (tooth rot related to poor dental hygiene), trauma, or failed dental root canal treatment. Left untreated these infections can be not only extremely painful but also pose a significant risk of descending into the deep neck space or ascending to intracranial sinuses. Identifying, treating, and educating patients about dental abscesses grants symptomatic relief and can prevent dangerous complications.[1][2]

Etiology

Dental caries, trauma, and poor dental hygiene are the most frequent causes of dental abscesses. A breakdown in the protective enamel of teeth allows oropharyngeal bacteria to enter the tooth cavity (pulp cavity), causing a local infection. See Image. Illustration of a Molar With Cavity and a Dental Abscess.

As this infection within the pulp cavity grows within the limited space of the tooth, it compresses the inner dentine walls, causing severe pain. This infection then tracks down through the root canal and inferiorly into the mandible or superiorly into the maxilla, depending on the location of the infected tooth. Another cause that predisposes individuals to a dental abscess is a partially erupted tooth, most commonly a wisdom tooth, where bacteria get trapped between the crown and soft tissues, causing inflammation. Other causes include genetic causes such as imperfect amelogenesis, which predisposes individuals to weakened enamel and makes them more susceptible to wear. Mechanical causes tooth grinding to break down tooth enamel. Medical conditions like Sjogren syndrome cause dry mouth, accelerating oropharyngeal microbial growth. Chemical irritants such as smoke from methamphetamine, immunosuppression arising from chemotherapy, or chronic immunosuppressive medical conditions such as HIV/AIDs can predispose individuals to dental caries.[3][4]

Epidemiology

Dental caries and poor dental health are quite common in the United States. Data from the National Health and Nutrition Examination Survey from 2011 to 2012, conducted by the National Center for Health Statistics for dental caries and tooth loss, reported that 91% of adults aged 20 to 64 had dental caries. These rates were lower for Hispanic, non-Hispanic black Americans, and non-Hispanic Asian adults when compared with non-Hispanic white adults (Dye et al 2012). Approximately 27% of adults aged 20 to 64 have untreated tooth decay. Rates of untreated tooth decay were higher in Hispanics at 36% and non-Hispanic Black Americans at 42% (Dye et al 2012). Of adults over 65, approximately 19% had untreated dental caries (Dye et al 2012).

A dental abscess and dental-related hospital emergency room visits are quite common. One study found that dental infection admissions in hospitals occurred at the rate of 1 per 2600 per population in the United States (Wang et al, 2005). The rates for pediatric emergency room visits are significantly higher for a dental abscess at 47 % (Graham et al, 2000). This data is not only suggestive of the very high prevalence of poor dental health, which is a major predisposing factor to developing a dental abscess, but it also shows that there are racial and likely socioeconomic factors at play. Provider practices may shift because of the community's population, racial distribution, and socioeconomic demographics.[5][6]

Pathophysiology

Tooth Anatomy and Structure

The tooth's anatomy consists of the crown, which is connected to the root and extends into the gum and jaw. The outermost covering of the tooth, the enamel, overlays the softer dentine. The nerves and vasculature tunnel through the tooth root canal to the innermost hollow area of the tooth called the pulp canal, which houses nerves and vasculature that supply the tooth.

Oral Cavity Flora

The oral cavity hosts many bacteria, mainly gram-negative and facultative anaerobes. These bacteria have varying distributions in the cavity; in particular, Streptococcus mitis was most typically found on tooth surfaces (Jorn et al 2005). This is not always the causative organism in a dental abscess because other oral bacterial species can become introduced into the tooth by other means, including, but not limited to, trauma.

History and Physical

A dental abscess should be considered when patients report severe pain, admit to poor dental hygiene and lack of adequate dental follow-up, admit to dental trauma that was not repaired, localized pain that is reproducible with palpation, facial erythema, trismus, dysphagia, fever, lymphadenopathy. Signs that should immediately illicit concern are altered mental status and dyspnea. When examining the oral cavity, the suspected tooth or teeth harboring infection may be discolored, have visual breaks in the enamel, or be surrounded by gingival erythema and swelling.

Evaluation

CT and MRI are sensitive modalities in detecting abscesses. Initial workup should include an x-ray of the head and neck and a complete blood cell count. X-rays of the head and neck can help identify compression or deviation of the trachea and subcutaneous air related to necrotic tissue. These imaging modalities can be useful if there is a need to evaluate possible ascending bacterial spread to the sinus cavities. A complete blood cell count can help rule out infectious etiology based on the total white blood cell count and the predominant white blood cell line that appears. There should be an increase in neutrophil count for bacterial infections in individuals who are not immunocompromised.

Treatment / Management

Treatment involves draining the abscess, providing antibiotic support, controlling pain, and removing infectious tooth sources. Often, oral antibiotics with timely dentist appointments for dental care interventions are sufficient. Dental abscesses may not require admission to the hospital and administration of intravenous antibiotics unless the patient presents with worrisome features that include fever, dyspnea, or airway compromise secondary to swelling. Most dental abscesses can be treated with antibiotics to cover gram negatives, facultative anaerobes, and strict anaerobes.[1]

Penicillins and cephalosporins can be used in odontogenic infections, but there is increasing antimicrobial resistance due to B-lactamase production. This increase in resistance would make using penicillins with other antimicrobials, such as metronidazole or an antibiotic with an extended spectrum, like ampicillin-sulbactam and ampicillin-clavulanate, more appropriate. 

• Dosing: Ampicillin-sulbactam 3 g intravenously every 6 hours
• Dosing: Amoxicillin-clavulanate: 875 mg orally every 12 hours
• Dosing: Penicillin G 2 to 4  intravenously every 4 to 6 hours PLUS Metronidazole 500 mg intravenously or orally every 8 hours
• Dosing: Cefoxitin: 1 to 2 g intravenously every 4 hours
• Dosing: Cefotetan: 2 g intravenously every 12 hours

Macrolides should not be used in the first line unless the patient has a penicillin or cephalosporin allergy. There is increased resistance to macrolides, and the bacterial species that exhibit resistance are anaerobic Streptococci and Prevotella species, which are major colonizers of the oropharynx and often culprits in a dental abscess.

Metronidazole has excellent coverage against anaerobic organisms but lacks sufficient coverage against aerobic gram-positive organisms. To extend antimicrobial coverage to include aerobic gram-positive organisms, it is recommended to use metronidazole in conjunction with penicillin.

• Dosing: Penicillin G 2 to 4 intravenously every 4 to 6 hours PLUS Metronidazole 500 mg intravenously or orally every 8 hours

Clindamycin is a good option for patients with allergies to penicillins and cephalosporins. It provides coverage against gram-positive organisms, anaerobes, and B-lactam-resistant organisms and has good bone penetration. It was demonstrated that Clindamycin was equally as effective in treating severe odontogenic infections as Penicillin V (Gilmore et al).

• Dosing: Clindamycin 600 mg intravenously every 6 to 8 hours   

For severe infections or immunocompromised patients, anti-pseudomonal antibiotics like fourth-generation or higher cephalosporins or extended-spectrum penicillins like piperacillin-tazobactam should be considered. Carbapenems like meropenem should also be reserved for severe infections. Meropenem has activity against gram-positive and gram-negative organisms as well as resistant organisms.

• Dosing: Piperacillin-tazobactam 4.5 g intravenously every 6 hours
• Dosing: Meropenem 1 g intravenously every 8 hours
• Dosing: Cefepime 1 to 2 g intravenously every 12 hours

Differential Diagnosis

The differential diagnoses for dental abscesses include:

• Buccal bifurcation cyst
• Eosinophilic granuloma
• Gingival abscess
• Langerhans cells histiocytosis
• Lateral periodontal cyst
• Osteomyelitis
• Periapical abscess
• Peritonsillar abscess
• Periapical granuloma or cyst
• Vertical root fracture

Surgical Oncology

Surgical management of a dental abscess can include a root canal or tooth extraction. If there is a periapical dental abscess, it may require incision and drainage. Incision and drainage can be performed in the emergency department or the clinic but must be followed by a dentist. A root canal is a procedure dentists perform where the tooth crown is removed, revealing the infected tooth roots. These passages are opened with surgical tools and cleaned with a solution. The tooth root is then filled, and the tooth crown is replaced. Complications include breaking surgical tools off inside of tooth root canal, cracked tooth, or incomplete evacuation of bacteria. These complications may require repeat root canals or tooth extraction.

Prognosis

The prognosis for a dental abscess is very good. However, if the abscess is left untreated, the prognosis can be quite poor; the mortality rate can increase to 40% if patients develop mediastinitis from descending infection (Shweta et al 2013). Airway compromise may warrant intubation or placement of a tracheostomy. Ascending infections through the sinuses or hematogenous spread to the brain increase the mortality rate and carry a poor prognosis.

Consultations

For complicated dental abscesses, consult maxillofacial surgery or a dentist if there is 1 on staff. 

Enhancing Healthcare Team Outcomes

Patients with a dental abscess usually present with oral cavity pain, fever, and difficulty chewing. Healthcare workers outside the dental profession should promptly refer these patients to an oral surgeon. Besides antibiotics, most patients also require an initial drainage procedure, to be followed for a formal dental procedure at a later date. For those patients who seek care promptly, the prognosis is good. However, any delay in treatment can lead to worsening of the problem and even loss of the tooth.

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References

1.

Stephens MB, Wiedemer JP, Kushner GM. Dental Problems in Primary Care. Am Fam Physician. 2018 Dec 01;98(11):654-660. [PubMed: 30485039]

2.

Roberts RM, Hersh AL, Shapiro DJ, Fleming-Dutra KE, Hicks LA. Antibiotic Prescriptions Associated With Dental-Related Emergency Department Visits. Ann Emerg Med. 2019 Jul;74(1):45-49. [PMC free article: PMC6943909] [PubMed: 30392733]

3.

Jenkins GW, Bresnen D, Jenkins E, Mullen N. Dental Abscess in Pediatric Patients: A Marker of Neglect. Pediatr Emerg Care. 2018 Nov;34(11):774-777. [PubMed: 30211838]

4.

Neves ÉTB, Perazzo MF, Gomes MC, Ribeiro ILA, Paiva SM, Granville-Garcia AF. Association between sense of coherence and untreated dental caries in preschoolers: a cross-sectional study. Int Dent J. 2019 Apr;69(2):141-149. [PMC free article: PMC9379004] [PubMed: 30246860]

5.

Sudan J, Sogi GM, Veeresha LK. Assessing clinical sequelae of untreated caries among 5-, 12-, and 15-year-old school children in ambala district: A cross-sectional study. J Indian Soc Pedod Prev Dent. 2018 Jan-Mar;36(1):15-20. [PubMed: 29607833]

6.

Burczyńska A, Strużycka I, Dziewit Ł, Wróblewska M. Periapical abscess – etiology, pathogenesis and epidemiology. Przegl Epidemiol. 2017;71(3):417-428. [PubMed: 29186939]

Disclosure: Justin Sanders declares no relevant financial relationships with ineligible companies.

Disclosure: Richard Houck declares no relevant financial relationships with ineligible companies.