Canker Sore

Aka: Canker Sore, Aphthous Ulcer, Aphthous Stomatitis, Minor Aphthae, Herpetiform Aphthous Stomatitis, Sutton's Aphthae, Major Aphthae

1. See Also
   1. Oral Ulcer
   2. Oral Lesion
2. Epidemiology
   1. Prevalence: 5-21% in United States
   2. Most common ulcerative condition of the oropharynx
   3. Family History in 40% of patients
   4. Age
      1. Peaks ages 10 to 20 years old
      2. Prevalence decreases after age 50 years
3. Pathophysiology
   1. Benign Autoimmune Condition
   2. Inflammatory Bowel Disease and Celiac Sprue may predispose to Aphthous Ulcers
   3. Nutritional deficiency may contribute in some cases
      1. Iron Deficiency Anemia
      2. Vitamin B12 Deficiency or Folic Acid Deficiency
4. Types
   1. Minor Aphthae (75 to 85% of cases)
      1. Painful ulcers <1 cm in size
      2. Persist 7-14 days
      3. Resolve spontaneously without scarring
   2. Herpetiform Aphthae (5 to 10% of cases)
      1. Patches of up to 100 small (1-3 mm) ulcers occurring throughout the oral cavity
      2. Persist 7-14 days (similar to Minor Aphthae)
      3. Resolve spontaneously without scarring (similar to Minor Aphthae)
   3. Major Aphthae or Sutton Disease (5 to 10% of cases)
      1. Painful ulcers >1 cm
      2. Persist up to 6 weeks
      3. Associated with HIV Infection
      4. Resolve spontaneously WITH mucosal scarring risk
5. Symptoms
   1. Multiple painful Oral Ulcers
6. Signs: Minor Aphthae
   1. Small round or oval white ulcer 1-5 mm in size
      1. White or yellow pseudomembrane covers center
      2. Surrounded by halo of reddened mucosa
      3. Typically less than 1 cm in size (except in cases of Major Aphthae)
   2. Distribution
      1. Single or multiple ulcers may coalesce
      2. Forms on nonkeratinizing oral mucus membranes
         1. Labial mucosa
         2. Buccal mucosa
         3. Ventral Tongue
7. Course
   1. See types above
8. Differential Diagnosis
   1. See Oral Ulcer
   2. See Oral Lesion
   3. Primary Herpetic Gingivostomatitis
   4. Herpangina
   5. Hand Foot and Mouth Disease
   6. Behcet's Syndrome
   7. Reiter's Syndrome
   8. Inflammatory Bowel Disease
   9. Celiac Sprue
   10. PFAPA Syndrome
       1. Periodic Fever
       2. Aphthous Stomatitis
       3. Pharyngitis
       4. Cervical Adenitis
9. Management: General
   1. Good Oral Hygiene
   2. Avoid Toothpaste containing Sodium Lauryl Sulfate (SLS)
      1. Aphthous Ulcer recurrence associated with use
      2. Reference
         1. Herlofson (1994) Acta Odontol Scand 52:257-9 [PubMed]
   3. Chlorhexidine gluconate (Peridex) mouthwash
      1. Reduces severity of episode
      2. Prolonged use may stain teeth
10. Management: Controlling Pain
    1. Topical Anesthetic
       1. Precautions
          1. Avoid extensive use over too wide an area
             1. May cause cotton-mouth feeling or taste loss
             2. May be worse than original problem
          2. Avoid in young children
             1. Risk of Seizures with Lidocaine
             2. Risk of Methemoglobinemia with benzocaine
       2. Dyclonine HCl Solution provides numbing for 1 hour
       3. Lidocaine (Xylocaine, ointment 5% or viscous)
       4. Diphenhydramine HCl (Benadryl elixir)
          1. Alone or with Kaopectate
       5. Anesthetic (Benzocaine) in Denture-like adhesive:
          1. Benzodent
          2. Orajel Denture
    2. Silver Nitrate Stick
       1. Destroys local nerve endings
       2. Provides pain relief for duration of eruption
       3. Ulcers may enlarge and heal more slowly
    3. Coat lesions
       1. Carafate (Sucralfate)
       2. Canker Cover
    4. Clean region after meals (may prevent irritation)
       1. Peroxide rinses (Peroxyl or Hydrogen Peroxide 3% diluted 1:1 with water)
    5. Magic Mouthwash
       1. Example: Mix of viscous Lidocaine, Benadryl, maalox with or without a Corticosteroid
11. Management: Aborting Lesions and shortening course
    1. Topical Corticosteroids
       1. Kenalog 0.1% in Orabase applied qid
       2. Allow Corticosteroid tablet to dissolve at lesion qid
          1. HydrocortisoneSodium Succinate 2.5 mg
          2. Betamethasone 17-valeraet 0.1 mg
       3. Aphthasol (Amlexanox 5% oral paste)
          1. Applied to lesions after meals and at bedtime
       4. Oral Steroid rinse
          1. Dexamethasone elixir mouth rinses (swish and spit)
       5. Debacterol
          1. Cotton swab with hollow handle containing sulfuric acid and phenol.
          2. Applied for 5-10 seconds (stings)
          3. Rinse vigorously afterward
          4. (2018) David Johnson, MD, per correspondence received 6/10/2018
          5. Rhodus (1998) Quintessence Int 29(12):769-73 +PMID: 10196853 [PubMed]
    2. Suppress oral streptococci
       1. Not recommended typically (listed for historical reasons)
       2. Saturate gauze pledget with antibiotic
       3. Dissolve in 30 cc water or elixir of Benadryl
          1. Tetracycline 250 to 100 mg or
          2. Keflex 250 mg
       4. Apply for 10-20 minutes 4-6 times/day for 5-7 days
12. Management: Severe, recurrent Aphthous Ulcers (medications used historically)
    1. Systemic Corticosteroids
       1. Precaution: May exacerbate conditions in differential diagnosis (HSV, Thrush)
       2. Taken for 4 days during prodromal period OR
       3. Prednisone 60 mg orally daily tapered off over 2-3 weeks
    2. Colchicine 0.6-1.8 mg orally daily
       1. Response in 4-6 weeks
       2. Significant toxicity
    3. Phenelzine (MAO inhibitor)
       1. Strict dietary and concurrent medication limits
    4. Dapsone
    5. Thalidomide
       1. High risk medication (highly Teratogenic, category X in pregnancy)
       2. May be useful in severe cases in HIV patients
13. References
    1. (2013) Presc Lett 20(1): 4
    2. Porter (2005) Clin Evid 13:1687-94 [PubMed]
    3. Gonsalves (2007) Am Fam Physician 75:501-7 [PubMed]
    4. Randall (2022) Am Fam Physician 105(4): 369-76 [PubMed]