Aphthous / Mouth Ulcers or Canker Sores

What Are Canker Sores?

An aphthous ulcer, also known as a canker sore, is a type of oral ulcer, which presents as a painful, shallow open sore inside the mouth, at the base of the gums or upper throat. Unlike cold sores, canker sores don't occur on the surface of your lips and aren't contagious.

Prevalence: 20%-40% of the U.S. population
Most Common: Adolescence and young adulthood

🔍 Key Differences

Canker sores and cold sores or fever blisters are often confused. Fever blisters typically appear outside the mouth (around the lips), while canker sores occur inside the mouth. Also, unlike canker sores, fever blisters are caused by a virus and are extremely contagious.

🩹 Types & Symptoms

Initial Symptoms

Aphthous ulcers are sores inside your mouth - on the tongue, soft palate (the back portion of the roof of your mouth), or inside your cheeks. They usually begin with a tingling or burning sensation at the site of the ulcer prior to its appearance. In a few days, may progress to form a red spot or bump, followed by an open ulcer.

🟡 Minor Canker Sores

  • • Oval, yellowish or grayish
  • • White center, red border
  • • 2-10mm in size
  • • Heal in 3-14 days
  • • No scarring

🔴 Major Canker Ulcers

  • • Similar appearance to minor
  • • Larger than 10mm
  • • Extremely painful
  • • Month+ to heal
  • • May leave scars

🟣 Herpetiform Ulcerations

  • • Resemble herpes infections
  • • Small, numerous (1-3mm)
  • • Form large clusters
  • • 7-10 days duration
  • • No scarring

Additional Symptoms

May include fever, physical sluggishness, and swollen lymph nodes. Canker sores commonly recur - some people have a few outbreaks a year, while others can have them almost constantly.

⚡ Potential Causes & Triggers

🍊 Dietary Triggers

  • • Citrus fruits (oranges, lemons)
  • • Hot beverages or foods
  • • Cow's milk allergies
  • • Gluten (Celiac disease)

🏥 Physical Factors

  • • Toothbrush abrasions
  • • Sharp/abrasive foods
  • • Accidental biting
  • • Dental braces
  • • Chemical irritants

🧠 Systemic Factors

  • • Stress and hormonal changes
  • • Lack of sleep
  • • Sudden weight loss
  • • Immune system reactions

💊 Nutritional Deficiencies

  • • Vitamin B12 deficiency
  • • Iron deficiency
  • • Folic acid deficiency
  • • Certain medications

⚠️ Underlying Medical Conditions

Less commonly, mouth sores can indicate:

Crohn's Disease Autoimmune diseases Bleeding disorders Cancer Weakened immune system Infections

🏠 Home Treatments

Good News:

Pain from a canker sore generally lessens in a few days and the sores usually heal without treatment in about a week or two. However, there are things you can do to relieve discomfort and expedite healing.

🛡️ Protect the Wound

  • Avoid poorly fitting dentures or braces
  • Avoid spicy or acidic foods
  • Brush gently with soft-bristled brush
  • Consider topical ointment as protective barrier

🧪 Rinse Solutions

  • Hydrogen peroxide mix: 1:1 with water
  • Salt & baking soda: 1 tsp each in 4 oz water
  • Baking soda paste: Mix with water

Rinse 4x daily, don't swallow!

🌿 Natural Remedies

  • Black tea bags: Contains pain-relieving tannin
  • Milk of magnesia: Apply topically
  • Lysine supplements: Speeds healing
  • Licorice root: Reduces ulcer growth

💊 Vitamin B12 Treatment

Proven effective: 1 mg dissolved under the tongue each evening has been found effective in treating recurrent aphthous ulcers, regardless of whether there is a vitamin deficiency present.

Reference: Volkov I, et al. (2009). J Am Board Fam Med 22(1): 9–16.

🩺 When to Consult Your Doctor

Seek medical attention if you have:

  • Compromised immune system (HIV, organ transplant, cancer treatment)
  • Unusually large or spreading sores
  • Sores lasting 2+ weeks
  • Intolerable pain despite treatment
  • Difficulty drinking enough fluids
  • Fever, skin rash, or drooling
  • Sores after starting new medication

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