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Common Mouth Sores and Patches

Anyone who has had a mouth sore knows it can be painful and can interfere with eating. Loose orthodontic wires, dentures that no longer fit or a sharp edge from a broken tooth or filling also can cause a mouth sore. Mouth sores also may be caused by bacterial, viral or fungal infections, which may be a symptom of a systemic disease or disorder. Some of the most common sores often associated with diseases and disorders are canker sores, cold sores and candidiasis. Make sure to stay well-nourished and hydrated while these sores heal.

Canker Sores

Canker sores, or aphthous ulcers, are very common, but they are not contagious. They are small, creamy-white ulcers with a red border that are quite painful. They often are confused with cold sores; however, while cold sores usually occur outside the mouth, canker sores always occur inside the mouth.

The exact cause of canker sores is uncertain, but some experts believe that immune system reaction may be involved. Fatigue, stress or allergies may increase the likelihood of canker sores.

Canker sores usually heal in a week or two, but recurrent outbreaks are common. If you have a canker sore, for your comfort, you should avoid hot, spicy or acidic food. Prescription drugs are available for the treatment of these sores from your dentist. There also are some over-the-counter topical medications that may provide temporary relief.

Cold Sores

Cold sores, which also are called fever blisters or herpes simplex, are groups of painful, fluid-filled blisters that erupt often around the lips and sometimes under the nose or around the chin. They usually are caused by herpes simplex virus type I and are very contagious (in other words, infectious).

Once a person has a primary herpes infection, which usually occurs before adulthood, the virus stays in the body and may cause recurrent attacks, which are characterized by tiny blisters that appear on the edge of the lips or sometimes inside the mouth. Blisters sometimes appear after a fever, sunburn, skin abrasions or emotional upset.

Cold sores usually heal in one to two weeks. Prescription and over-the-counter creams may provide relief. In more severe cases, antiviral drugs may be prescribed.

Candidiasis

Candidiasis is a fungal infection that results in red-and-cream-colored patches that form on moist surfaces in the mouth and can be painful. The condition may cause difficulty in swallowing and change the sense of taste.

Candidiasis most often occurs in people who are very young or elderly, in people debilitated by disease or in people who have an improperly functioning immune system. It may result from antibiotic treatment, which decreases the normal bacteria in the mouth.

Treatment consists of controlling the conditions that caused the outbreak. Because candidiasis is common among denture-wearers, a thorough daily cleaning of dentures is important. Removing dentures at night also allows the denture-bearing tissues to regenerate.

If antibiotics are the culprit, talk to your doctor about reducing your dosage or changing the treatment. Saliva substitutes or prescription medications can help. Antifungal medications may be used to help manage or resolve the condition. Good oral hygiene is essential.

American Dental Association

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