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All About Mouth Ulcers: Causes & Treatments

12 October 2017

Most people have mouth ulcers at some time or another. They can interfere with smiling, eating and look unsightly. Mouth ulcers can be caused by:

  • Ill fitting dentures
  • Bacteria
  • Braces
  • Disease
  • Sharp edge of a chipped tooth
  • Fungal or viral infection

Types of Mouth Ulcers

There are three typical types of ulcers that commonly occur in the mouth. They are classified as:

1. Minor Ulcers

These are small ulcers not more than 1cm in diameter, usually ranging in colour from light pink to white.

2. Major Ulcers

An ulcer that's bigger than 1cm in diameter and/or is much darker in colour than a typical minor ulcer may be classified as a major ulcer.

3. Herpetiform Ulcers

A tight cluster of ulcers of viral origin. Although the name implies HSV (Herpes Simplex Virus) as a cause, there are other virus organisms that can create herpetiform ulcers, including CVA16 and EV71.

Because blisters and ulcers are closely related and similar in appearance, it is possible to mistake a blister for an ulcer.

However, it's important to note that unlike ulcers, blisters are usually caused by burns or scalds. Additionally, ulcers won't normally leave scar tissue behind, while blisters may or may not, depending on their severity.

Causes of Mouth Ulcers

Ulcers can be caused by a variety of factors, and some causes of ulcers are still unknown. Common causes include:

  • Trauma
  • Allergic reactions
  • Hormonal reactions
  • Immune system disorders
  • Diseases
  • Methamphetamine use (when smoked)
  • Starting or stopping cigarette smoking
  • Some heart medications and NSAIDs, including Ibuprofen and Aspirin.

In addition to those mentioned above, nutritional deficiency is a common cause of mouth ulcers. Vitamin C deficiency, if severe will lead to scurvy, which causes ulcers, tooth loss and other problems affecting the mouth.

There is some evidence to suggest that deficiencies in Vitamin B12 and Iron may also contribute to the formation of mouth ulcers. This could mean people following an exclusively vegan diet may be at an increased risk of developing mouth ulcers.

Often people worry about cancer being a contributing facor, however, this is the least likely cause. Therefore, you should not worry unnecessarily.

If the ulcer is present for more than a week or two and/or if it changes size, shape, or colour, you should then seek a medical diagnosis.

How to Treat Mouth Ulcers

Most ulcers will go away if you simply ignore them but if you'd rather hasten them on their way, some or all of the following tips will usually help:

  • Take a supplement containing Vitamin C, Vitamin B12, zinc, iron or folate.
  • Use a mild antiseptic mouthwash. Alcohol-free choices are probably best.
  • Brush your teeth with the softest toothbrush you can find.
  • Avoid "bothering" the ulcer. You may remove more protective skin tissue if you disrupt it.
  • Eat celery as it contains nutrients and natural anti-inflammatory substances.
  • As honey is anti-microbial and moisturising, apply a small amount of honey to the surface of the ulcer with a Q-tip. Aloe vera can be used in the same way but most people find the taste less pleasant than honey.

For more serious ulcers, which are causing a lot of discomfort, you may need to:

  • Use hydrocortisone lozenges (sparingly), being aware of potential side-effects
  • Use non-prescription or prescription pain killers (but not Ibuprofen or Aspirin)
  • Visit your dentist for a dental check-up 

It's important to remember that ulcers often seem like a serious problem, but most of the time they're not.

In children, you do need to be a little more proactive about getting that check up because there is always the possibility of HFMD (Hand, Foot & Mouth Disease). 

Otherwise you only need to worry if your ulcer is very persistent, is excessively painful, undergoes significant negative changes, or is accompanied by other symptoms (such as a rash or fever).

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