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Mouth Sores 

Mouth sores are a common condition.  There are several different types of mouth sores.  The most common types include canker sores, cold sores, leukoplakia, and candidiasis.  Some develop inside of the mouth and others develop on the lips and skin surrounding the mouth.  They can cause pain and discomfort. Medications are used to relieve the symptoms of mouth sores and help them heal.

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Mouth sores can develop inside or outside of the mouth.  They may develop on the inner cheeks, gums, lips, tongue, or the roof of the mouth.  They may develop on the outer lips or skin surrounding the lips.

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There are several types and causes of mouth sores.  Common conditions include canker sores, cold sores, leukoplakia, and candidiasis.  The cause of canker sores is unknown.   Researchers suspect viruses, bacteria, or immune system problems cause them.  However, other factors including smoking, trauma, allergies, stress, nutritional deficiency, and heredity appear to contribute to the development of canker sores.  Additionally, people with certain gastrointestinal disorders, such as ulcerative colitis or Crohn’s disease, may be prone to canker sores or aphthous ulcers.

Cold sores are also called fever blisters or herpes simplex.  Cold sores are usually caused by the herpes simplex I virus. Cold sores are highly contagious.

Leukoplakia results from excess cell growth.  Leukoplakia is considered a precancerous condition and can lead to cancer.  It can result from irritants in the mouth including smoking, chewing tobacco, poor fitting dentures, broken teeth, or the habit of chewing on your cheek.  It may also be one of the first signs of HIV, the virus that causes AIDS.

Candidiasis is also called moniliasis or oral thrush.  Candidiasis is a fungal infection caused by candida albicans, a yeast.  It is common among denture wearers and newborns.  In some people, it may occur after treatment with certain antibiotics.  People with dry mouth are especially susceptible to the fungus.  Candidiasis can repeatedly affect people with immune system disorders, including HIV, AIDS, and cancer.

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Canker sores occur inside of the mouth.  Canker sores look like small white swollen areas or sores.  The sores may be surrounded by redness.  They may hurt or cause mild discomfort.  Canker sores are common and can reappear.  They are not contagious.
Cold sores appear on the outside of the mouth, the edges of the lips, and skin below the nose or lips.  They frequently develop in clusters.  Cold sores first appear as fluid-filled blisters.  They can be painful and unsightly.  Cold sore episodes may recur or once infected; a person may just carry the virus.  Cold sores are highly contagious.
Leukoplakia occurs inside of the mouth on the tongue, gums, cheeks, or lips.  It looks like a thick, slightly raised, white or gray colored patch.  Hairy leukoplakia, associated with HIV, appears as fuzzy white patches on the tongue.
Candidiasis occurs inside of the mouth on the tongue, gums, cheeks, or lips.  Candidiasis looks like creamy white-yellow colored areas, red patches, or a combination of both.  The affected areas can be painful.

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Your doctor can diagnose mouth sores and determine which type you have.  You should tell your doctor about your medical history, risk factors, and symptoms.  Your doctor will examine the inside and outside of your mouth.  Blood tests and cultures may be taken to confirm the diagnosis if necessary.  A biopsy (tissue or cell sample) may be taken to check for cancer or precancerous cells.

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Treatment depends on the type of mouth sore that you have.  Canker sores usually heal on their own in one to two weeks.  Over-the-counter medications and rinses can provide pain relief.  You should avoid hot, spicy, or acidic foods that cause irritation.

Cold sores usually heal in about a week.  There is no cure for herpes simplex I.  Over-the-counter medications can provide symptom relief.  Your doctor can prescribe antiviral medications that may help reduce the outbreaks.

Removing the irritant that causes the lesions treats leukoplakia.  You may need to stop smoking or get new dentures.  Your doctor will monitor the affected site and take a biopsy.  Your doctor will explain treatment options for precancerous and cancerous conditions.

Removing or controlling the factors that cause it treats candidiasis.  You should brush and floss your teeth according to your dentist’s or doctor’s instructions.  Clean your dentures thoroughly.  Do not wear dentures at night.  If you have dry mouth, saliva substitutes can help.  If your candidiasis is caused by a side effect from prescription medication or an underlying medical condition, talk to your dentist or doctor about treatments to combat the condition and relieve your symptoms.

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It can be helpful to practice good oral hygiene and receive regular dental check-ups and cleaning.  Contact your dentist if your dentures do not fit properly.  You should stop using smoking or chewing tobacco products.  Avoid direct contact with people that have contagious mouth sores.

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Am I at Risk

Risk factors for mouth sores:

_____ People with immune suppressing conditions, such as HIV, AIDS, and cancer have an increased risk for developing mouth sores, particularly leukoplakia and candidiasis.
_____ Cold sores are highly contagious and can be spread by contact between people.
_____ Smoking or chewing tobacco products increases the risk of mouth sores and precancerous conditions.
_____ Poor fitting dentures, poor oral hygiene, or mouth trauma increases the risk of mouth sores.
_____ Certain gastrointestinal disorders, allergies, stress, heredity, and nutritional deficiencies may contribute to the development of mouth sores.
_____ Certain medications, such as some antibiotics, increases the risk of mouth sores.

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Leukoplakia is considered a precancerous condition.  Mouth sores are associated with an increased risk of oral cancer and dental infections.  People with HIV, AIDS, or cancer may experience repeated episodes of leukoplakia and candidiasis.

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This information is intended for educational and informational purposes only. It should not be used in place of an individual consultation or examination or replace the advice of your health care professional and should not be relied upon to determine diagnosis or course of treatment.

The iHealthSpot patient education library was written collaboratively by the iHealthSpot editorial team which includes Senior Medical Authors Dr. Mary Car-Blanchard, OTD/OTR/L and Valerie K. Clark, and the following editorial advisors: Steve Meadows, MD, Ernie F. Soto, DDS, Ronald J. Glatzer, MD, Jonathan Rosenberg, MD, Christopher M. Nolte, MD, David Applebaum, MD, Jonathan M. Tarrash, MD, and Paula Soto, RN/BSN. This content complies with the HONcode standard for trustworthy health information. The library commenced development on September 1, 2005 with the latest update/addition on April 13th, 2016. For information on iHealthSpot’s other services including medical website design, visit