Aphthous ulcer (aphtha = “mouth ulcer”) tends to be a misnomer.
That is, it is still in common use and is more accurately described in the literature as Recurrent Aphthous Stomatitis (RAS), due to its recurrent nature. It is also known as Recurrent Aphthous Ulcers or Canker Sores.

• Recurrent Aphthous Stomatitis (RAS) are ulcers of the oral mucosa that are painful, round, and have an erythematous “halo”.
• About 20% of the population is affected, with the peak age of onset between 10 – 19 years.
• Frequency declines with aging and may spontaneously disappear beyond 30 years.

RAS may present as Minor, Major, or Herpetiform ulceration, with most patients presenting in the latter two categories.

Minor Aphthous Ulcers:

• • • 80% of RAS.
    • Less than 1 cm.
    • Occur on nonkeratinized oral mucosae (Buccal/lip mucosae, floor of mouth, ventral surface of tongue).
    • Yellow-grayish pseudomembranous center.
    • Burning prodrome 1-2 days prior.
    • Heal spontaneously with no scarring in 10-14 days.

Major Aphthous Ulcers:

• • • Larger than 1 cm.
    • May occur on keratinized oral mucosae (Dorsum of tongue, hard palate).
    • May last weeks to months and heal with scarring.
  • Herpetiform Aphthous Ulcers:
    • Clusters of multiple pinpoint ulcers.
    • Occur scattered throughout the mouth.
    • Typically lasts less than 30 days and is unlikely to scar.
      

      Aphthous ulcer inside the lower lip. Author: TheBlunderbuss (Wikimedia Commons) License: CC BY SA 3.0/GFDL

• Precipitating factors:
  • Trauma to site.
  • Smoking cessation.
  • Anxiety or Stress.
  • Menstrual cycle hormonal changes.

• Diagnosis is based on:
  • History of recurrent ulcers.
  • Characteristic lesions (dependent on type of aphthous stomatitis).
    • Generally painful, yellow-grayish pseudomembranous center with erythematous halo.
• Ulcers lasting 3 weeks or longer require further work-up to rule out other serious causes.
• Lab investigations are not required UNLESS history and physical exam are highly suggestive of an alternate/secondary diagnosis such as:
  • Infectious:
    • Frequent recurrence, slower healing, and larger lesions suggest immunocompromised state.
  • Rheumatic:
    • Genital or other extraoral lesions.
    • Joint involvement.
  • Dermatological:
    • Cutaneous lesions.
    • Uncharacteristic shape of lesion.
  • Hematologic:
    • Recurrent fever.
    • Inflammation in other areas of the body.
    • Bone pain.
    • Anemia.
    • Petechiae or purpura.
  • Gastrointestinal:
    • Persistent diarrhea.
    • Weight loss.
    • Abdominal pain.
• Differential Diagnosis:
  • Infectious:
    • HIV.
    • Herpesvirus.
  • Rheumatic:
    • Behçet’s syndrome.
    • Reiter’s syndrome.
    • Sweet’s syndrome.
  • Dermatological:
    • Erythema multiforme.
    • Pemphigus or pemphigoid.
  • Hematologic:
    • Cyclic neutropenia.
    • Leukemias.
  • Gastrointestinal:
    • Celiac disease.
    • Inflammatory bowel disease (Ulcerative colitis, Crohn’s disease).
• Possible investigations guided by secondary findings:
  • CBC.
  • HIV/Other virologic testing.
  • Nutritional deficiencies (Vitamin B12, folate, iron).
  • Antigliadin/Transglutaminase antibodies.
  • C Reactive Protein/ESR.

• The goal of therapy is to reduce pain and inflammation.
  • Choice of therapy is based on the severity of pain, frequency, size, and number of ulcers.

Mild Symptoms

• • Patient education on avoiding trauma (e.g. hard foods).
  • First-line pharmacological treatment should be topical, and if ineffective, then systemic.
  • Pain management:
    • Topical analgesics:
      • 15% Benzydamine HCl oral rinse applied 4x daily for 2 weeks or until ulcer healed.
      • 5% Lidocaine gel applied 4x daily for 2 weeks or until ulcer healed.
    • Inflammation control:
      • Topical corticosteroids:
        • 1% Triamcinolone acetonide dental paste applied 4x daily for 2 weeks or until ulcer healed.
        • 05% Fluocinonide cream applied 4x daily for 2 weeks or until ulcer healed.
    • Frequency/Duration reduction:
      • Antimicrobial mouthwashes:
        • 12% Chlorhexidine gluconate mouthwash used 4x daily for 2 weeks or longer.

Severe Symptoms

• • Topical therapies (above) in combination with systemic corticosteroid treatment are recommended.
    • 30 – 60 mg Oral prednisone for 1 week, followed by 1-week taper.
  • Consider referral to a dental specialist.
• A 2012 Cochrane review of systemic therapies for aphthous stomatitis found no single effective treatment due to lack of drug trials or poor methodology for those that exist.

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