Canker Sores

A Pain in the Mouth Youtube sm

Canker sores affect millions of people. For some, canker sores are an occasional nuisance; while for others, they can be a continuous source of discomfort. If you’ve ever had a canker sore, you know it hurts.

The actual cause of these annoying mouth ulcers, technically known as aphthous stomatitis, is unknown. However, in some people, certain factors appear to trigger the onset of a canker sore.

Mouth injury/irritation
There are several everyday occurrences that can cause minor injuries to the inside of your mouth. At one time or another, we’ve all accidentally bitten our tongue or the inside of our lip. Other common incidences can include the following:

  • subconsciously biting the lips or the inside of the cheek
  • cutting the mouth or gums on food with sharp edges
  • having ill-fitting dentures or braces rub against and irritate the inside of the cheek or gum
  • brushing too vigorously

All of these injuries can open the door to canker sores by breaking the skin on the mouth’s mucus lining. When this happens, the mouth is more vulnerable to irritants that can cause canker sores.

Nutritional deficiencies
Several studies have indicated that canker sores are more common in individuals who are deficient in iron, folic acid, and other B vitamins. Vitamin supplements or an improved diet can eliminate these deficiencies; ask your doctor for a nutritional assessment.

Food irritation

Some people get canker sores when they eat certain things, indicating that they may be allergic to one or more foods. Eliminating the offending food can dramatically decrease canker sore outbreaks. But how do you find out which food provokes the mouth sores? Keep a journal of all the food you eat and note incidences of canker sores that occur; this should help identify the culprit. Some of the most common offenders are chocolate, mustard, nuts, tomatoes, shellfish, and pineapple.

Toothpaste with SLS
A common ingredient in many toothpastes might be linked to an increased occurrence of canker sores in some people. A study done in Norway linked SLS (sodium lauryl sulfate) to canker sore incidences. If you suspect that you have SLS sensitivity, try switching to an SLS-free toothpaste for a while and see if that helps.


Stress can have many negative effects on the body, and canker sores are one of them. Several studies have shown that individuals who lead extremely demanding, stressful lives have a higher incidence of canker sores. During stressful periods, the body’s immune system is affected. Scientists haven’t pinpointed the exact cause of this mind-body connection, but it’s safe to say you’ll garner numerous health benefits by reducing stress in your life, including losing those annoying canker sores.

There are no surefire cures currently available for canker sores; usually, you just have to let them run their course. However, there are several options for relieving canker sore pain. Consult with your dentist regarding which of the following remedies would work best for you:

  • Corticosteroids: These prescription gels or creams reduce the inflammation caused by canker sores.
  • Antibacterial mouthwashes: Only a few mouthwashes on the market have been clinically proven to reduce bacteria including, Listerine® and medicated mouthwashes that contain chlorhexidine gluconate. The latter ingredient can stain teeth, however, so use this only with the advice of your dentist or physician.
  • Pain-relieving (analgesic) gels: These contain the active ingredient benzocaine or diphenhydramine HCL to relieve pain; some even form a protective film over the canker sore. They are available over the counter. Stronger prescription analgesics are also available, especially those medications that contain 2 percent lidocaine.
  • Aphthasol: This medication, approved by the FDA, has been shown to reduce canker sore pain and shorten healing time.
  • Saltwater rinses: While questionable as an effective treatment for canker sores, rinsing with saltwater is completely safe and inexpensive, so give it a try. Just mix a teaspoon of salt in a cup of warm water, and gently swish the solution in your mouth for about a minute before you spit it out.
  • Herbal “tea” rinses: Naturopathic practitioners believe sage and thyme to be natural antiseptics. This has not been proven, but these herbs are safe and inexpensive. Immerse a few spoonfuls in a cup of hot water, allow the mixture to cool to room temperature, then rinse your mouth with it for about a minute and spit it out.
  • Acemannan hydrogel patch: Reports show that this treatment reduces the healing time, as well as the pain, of canker sores. The patch, which contains a form of aloe vera, has received FDA approval and is being sold as the Carrington Patch.
  • ORA5: This is a topical antibacterial compound that uses copper sulfate and iodine to cover the irritated area, greatly reducing the pain. It is relatively inexpensive (around $6) and is available without a prescription.

Why so much pain?

A sore on your mouth’s lining reacts differently than a sore on your skin. Because your mouth is a moist environment, the sore doesn’t dry out and scab over. This causes sensitive nerve endings to constantly be exposed to friction, foods, and beverages. Most canker sores heal within two weeks. If yours takes longer than that, or if it prevents you from eating or drinking, consult with your dentist.


Massachusetts Dental Society

Two Willow Street
Suite 200
Southborough, MA 01745

(800) 342-8747
(508) 480-0002 fax

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