Acute Necrotizing Ulcerative Gingivitis (ANUG)

Acute Necrotizing Ulcerative Gingivitis (ANUG) is a severe form of gingivitis characterized by rapid necrosis of the interdental papillae and gingival margins. Patients typically present with soreness, pain, bleeding gums, and a foul mouth odor (fetor-ex ore/halitosis).

ANUG is also referred to as Vincent’s gingivitis or Vincent’s gingivostomatitis. It commonly affects malnourished children, immunocompromised individuals, and patients with systemic conditions such as HIV/AIDS or diabetes mellitus. In severe cases, particularly in malnourished patients, the disease can progress to Cancrum Oris (noma), causing extensive facial and jaw tissue destruction.

Pathophysiology

ANUG develops due to a combination of bacterial infection, poor oral hygiene, and host immunodeficiency:

• Overgrowth of anaerobic bacteria (e.g., Fusobacterium, Prevotella intermedia, Treponema species) in the gingival sulcus

• Local tissue hypoxia and necrosis

• Inflammatory response with edema and ulceration

• Rapid destruction of interdental papillae

• In severe immunocompromised states, infection can extend to oral mucosa and facial tissues (noma)

Signs and Symptoms

• Painful, tender, and easily bleeding gingiva

• Swelling and erythema of gingival margins

• Yellowish-white ulcerations of interdental papillae

• Foul odor from mouth (halitosis)

• Fever, malaise, and regional lymphadenitis

• In severe malnutrition or immunodeficiency, progression to Cancrum Oris

Diagnostic Criteria

Diagnosis is primarily clinical, based on:

• Painful and bleeding gingiva with swollen and erythematous margins

• Yellowish-white necrotic ulcerations of interdental papillae

• Foul mouth odor (fetor-ex ore)

• Fever, malaise, and tender regional lymph nodes

• History of poor oral hygiene, malnutrition, or immunocompromised state

• Severe forms may show facial tissue necrosis (Cancrum Oris)

Investigations

• Typically not required for uncomplicated cases

• Microbiological culture may be considered in refractory or atypical cases

• Nutritional and immunological assessment in patients with systemic risk factors

Management

Non-Pharmacological Management

• Professional debridement and scaling of necrotic tissue under local anesthesia

• Removal of dental plaque and calculus

• Oral hygiene instruction for the patient

• Nutritional support for malnourished individuals

• Adequate hydration and supportive care in systemic illness

Pharmacological Management

• Hydrogen peroxide 3% for professional oral debridement

• Antibiotic therapy (for moderate to severe cases):

  • Metronidazole 400 mg orally every 8 hours for 5 daysAND

  • Amoxicillin 500 mg orally every 8 hours for 5 days

• Analgesics for pain control:

  • Paracetamol 1 g orally every 8 hours

  • Ibuprofen 400 mg orally every 8 hours (if no contraindications)

• For patients allergic to penicillin:

  • Clindamycin 300 mg orally every 8 hours for 5–7 days

Complications

• Progression to Cancrum Oris (noma) in malnourished or immunocompromised patients

• Extensive facial tissue necrosis

• Tooth loss due to rapid periodontal destruction

• Secondary bacterial infection

• Systemic infection if untreated

Prevention

• Maintain proper oral hygiene (tooth brushing and flossing)

• Early treatment of gingivitis

• Nutritional support, particularly in children

• Management of systemic conditions (HIV, diabetes, immunosuppression)

• Regular dental check-ups

• Avoid stress and ensure adequate sleep in high-risk patients

Prognosis

• Early treatment results in rapid resolution of pain and halitosis

• Healing is usually complete with minimal tissue loss if systemic risk factors are controlled

• Severe cases (Cancrum Oris) require multi-disciplinary care, including surgical reconstruction