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Canker Sores: Causes

Canker Sores
Canker Sore or Cold Sore?

Canker sore sufferers may confuse their symptoms with cold sores, or vice versa. Both types of sores cause pain and tingling, take a couple of days to form, and can strike several times a year. But the resemblance ends there. Canker sores only occur inside the mouth, while cold sores frequently appear on or around the outer lips. Canker sores also appear white or gray, while cold sores display blistering. Ask your dentist for an informed diagnosis.

Canker sores are nothing to smile about -- as you may already know. These small, uniformly-rounded sores can occur, several at once, on the inside of the mouth, affecting the cheeks, gums, lips, tongue and/or throat. If you've had to deal with recurring appearances by these painful intruders, you may wonder why you get them in the first place. The answer to that question is trickier than you might think.

Medical science doesn't currently have a catch-all explanation for exactly why some people are susceptible to canker sores while others are not. Research points out that there may be a combination of triggers at work; when the right combination of triggers coincide, outbreaks occur. This might be one reason why canker sores predominantly affect women between the ages of 10 and 20, since hormonal changes have been identified as a trigger. Emotional stresses can also contribute to outbreaks.

Canker sores may also appear in association with certain diseases, which has caused some speculation over whether a virus might be involved. People with suppressed or failing immune systems are known to be vulnerable to canker sores. Celiac disease, inflammatory bowel disease, and an inflammatory condition called Behcet's disease are possible culprits.

In fact, it also appears that the old phrase "you are what you eat" may apply to canker sores. Vitamin deficiencies due to poor diet may make the body more susceptible. Food allergies or sensitivities can irritate the mouth and bring on an attack of canker sores, especially when acidic foods are involved. The presence of certain varieties of oral bacteria may prompt outbreaks. Other oral triggers may include the constant rubbing of a dental or orthodontic appliance against the tissues of the mouth. If you use toothpaste made with sodium lauryl sulfate, a reaction to this substance could turn your daily efforts at good oral hygiene into recurring canker sore episodes.

What Can You Do About Canker Sores?

While there is no preventing the sores themselves, you can eliminate some of the potential triggers. Try switching to toothpaste containing different ingredients (as long as it's still approved by your dentist). Have yourself checked for hormonal imbalances, food allergies, or nutritional deficiencies. Find techniques to reduce stress. Consult your dentist for other suggestions on how you can best manage your canker cores.


Colgate, "Canker Sores (Aphthous Stomatitis Or Recurrent Mouth Ulcers)."

Mayo Clinic, "Disease and Conditions: Canker Sore.”

University of Michigan,"Cold and Canker Sores."

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