Managing a Patient with Pericoronitis



Pericoronitis is defined as an acute or chronic infection of the enveloping mucosa and gingiva of an incompletely erupted tooth. The bacteria commonly associated with pericoronitis are α-hemolytic streptococci such as Prevotella, Veillonella, Bacteroides and Capnocytophaga. Untreated, it can progress from a local infection to a significant life-threatening infection.



Any stage of adulthood when a tooth is only partially erupted. The incidence is highest among young adults between age 21–25, when third molars tend to erupt.


Acute pericoronitis

  • Swelling
  • Constant trauma to the inflamed gingiva: the edematous gingival tissue around the retromolar trigone may contact the opposing molars
  • Exacerbated halitosis due to the presence of anaerobic bacterial dwellers
  • Purulent discharge
  • Systemic signs such as regional lymphadenopathy and low-grade fever

Chronic pericoronitis

  • Periodontal pocketing may be the only sign of asymptomatic pericoronitis


  • Discomfort due to food impaction underneath the surrounding gingival tissue, physical tension, or bad taste and halitosis
  • Malaise
  • Pain severity: very painful in acute pericoronitis. Depending on the infection severity, pain can range from localized tenderness or discomfort to a severe throbbing pain radiating to the ear, nose, throat and head region.


  1. Confirm the presence of acute pericoronitis.
    • Molar and retromolar region involvement
    • Pain, spontaneous or provoked
    • Gingival swelling surrounding the involved tooth
    • Localized extraoral swelling
    • Bad taste and halitosis
    • Purulent discharge from the infected area
    • Trismus
  2. Monitor the patient’s comfort level and prescribe radiographs. Periapical radiographs and bitewings may confirm or exclude caries and pulpal involvement as the primary source of pain.
  3. Determine the severity of the pericoronitis and involvement of adjacent structures.
    • Verify the presence of Ludwig angina and/or facial cellulitis.
    • Look for facial swelling, tongue elevation, breathing difficulty, neck pain or swelling. If these are found, the patient should be directed to the nearest ER to secure the airways and start systemic administration of antibiotic therapy.


Based on the signs and clinical examination, a diagnosis of acute or chronic pericoronitis is determined.

Differential Diagnosis

  • Periodontal disease
  • Involvement of adjacent anatomic structures may trigger trismus, dysphagia, odynophagia and otalgia


Common Treatment Options

  1. Prescribe NSAIDs as a first line of treatment for localized cases.
  2. Perform debridement without local anesthesia, if the situation permits and pain is sustainable.
  3. Prescribe antibiotics to eliminate the bacterial charge: amoxicillin and clavulanic acid (125 mg every 12 hours for 7 days).
    Antimicrobial treatment is justified in the case of suppurative acute pericoronitis and for patients with high risk of infection.
  4. Surgically remove the involved molar after the acute infection has been controlled.
    Avoid major blunt dissection of the covering gingival tissue which can spread a superficial infection into the deep spaces of the head and neck.
  5. Instruct the patient to irrigate underneath the gingival tissue of the affected tooth with a weak (2%) hydrogen peroxide solution.
  6. Emphasize the importance of cleansing away any food that collects under the gingival flap.



Dr. Nuwwareh is a clinical research officer at the Canadian Agency for Drugs and Technologies in Health, specializing in periodontology and methodologies of clinical research and epidemiology.

Correspondence to: Dr. Samer Nuwwareh, 600–865 Carling Avenue, Ottawa, ON, Canada, K1S 5S8. Email:

The author has no declared financial interests.

This article has been peer reviewed.

Suggested Resources

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  3. Punwutikorn J, Waikakul A, Ochareon P. Symptoms of unerupted mandibular third molars. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1999;87(3):305-10.
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