How Do I Manage a Patient with an Extensive Odontogenic Infection?


Extensive Odontogenic Infection

Patients will be lethargic, in severe pain, have difficulty speaking or swallowing. Trismus is present most of the time.



  • Patients with poor oral hygiene
  • Patients who do not receive regular dental care
  • Immunocompromised patients (e.g., diabetes, HIV/AIDS, connective tissue disease)
  • Patients with restorations


  • Fever and lethargy
  • Trismus
  • Large swelling
  • Difficulty to speak and swallow
  • Inability to manage secretions (acute onset of drooling is a worrisome sign)
  • Inability to recline due to shortness of breath (worrisome sign)
  • Extensive caries
  • Tooth fracture
  • Tooth mobility


  • Moderate to severe pain
  • Swelling, often associated with surface redness
  • Limited mouth opening
  • Fever and malaise
  • Floor-of-the-mouth edema and decreased tongue mobility
  • Rapid and weak pulse


Rule Out Local Pathologies

  • Obtain a thorough medical history and record vital signs.
  • Inquire whether the patient is immunocompromised.
  • Obtain a thorough dental history and inquire about the history of pain (onset, location, duration, progression over time, type of pain).
  • Take intraoral and extraoral radiographs, pending on the patient’s cooperation and comfort level.
  • Investigate the degree of anatomical site involvement, ensuring that the spaces other than the oral cavity are intact.


Based on the clinical observations and investigation, a diagnosis of extensive odontogenic infection is determined.

Differential Diagnosis

Non-odontogenic infections (major salivary gland infections, peritonsillar abscesses, viral infections, cystic lesion infections)


Common Initial Treatments

  1. Eliminate the source of infection (e.g., the infected teeth).
  2. If the infection is fluctuant, aspirate to get samples and send for Gram staining and aerobic and anaerobic cultures.
  3. Incise and drain.
  4. Prescribe antibiotics:
    • IV antibiotics if the patient is in an urgent care facility
    • if the infection is mild to moderate, prescribe penicillin V 300–600 mg orally q.i.d. for at least 7 days (if the patient is allergic to penicillin, prescribe clindamycin 300–600 mg orally q.i.d. for 7 days), plus anaerobic coverage:
      • metronidazole (e.g., Flagyl®) 500 mg orally t.i.d. for 7 days; or
      • amoxicillin 500 mg orally t.i.d. for 7 days; or
      • amoxicillin with clavulanate potassium (e.g., Augmentin®) 500 mg orally t.i.d. for 7 days
  5. To successfully manage the pain, a combination of narcotics and anti-inflammatory drugs is recommended.


  • First line of referral should be to an oral surgeon to expedite patient’s treatment, as they have access to hospitals and have the option of performing in-office sedation (if patient’s safety is not compromised).
  • If an oral surgeon is not available, refer the patient to the hospital E.R. Contact the emergency doctor directly to convey your findings and ask whether you should prescribe antibiotics before referral.
  • Ensure the patient understands the severity of the condition and that it could lead to death if untreated or if seeing the specialist is delayed.
  • Emphasize the importance of completing the full dose of antibiotics.



Dr. Chemaly is an oral and maxillofacial surgeon who maintains a private practice in Toronto.

Correspondence to: Dr. Daisy Chemaly, Dr. Daisy Chemaly Dentistry Professional Corporation, 2-2416 Bloor Street West, Toronto, ON  M6S 1M8. Email:

The author has no declared financial interests.

This article has been peer reviewed.

Suggested Resources

  1. Miloro M, editor. Peterson’s Principles of Oral and Maxillofacial Surgery. 2nd ed. Hamilton: BC Decker Inc.; 2004.
  2. Topazian RG, Goldberg MH, Hupp JR. Oral and Maxillofacial Infections. 4th ed. Philadelphia: W.B Saunders Co.; 2002.