Canker Sores, Cold Sores and More

Painful open sores and lesions in the mouth aren't just annoying--they could be a symptom of a serious disease or disorder. See your dentist for any mouth sore that lasts longer than a week.

Canker sores and cold sores are the most common types of mouth sores.

Canker sores are small ulcers with a white or gray base and a red border that aren't contagious and appear inside the mouth. The exact cause of canker sores is unknown but some experts believe they are caused by immune system problems. Canker sores can be triggered by a viral infection, fatigue, stress or allergies. If you suffer from canker sores, over-the-counter topical anesthetics and antimicrobial mouthrinses may provide temporary relief. It's also helpful to stay away from hot, spicy or acidic foods that can irritate the sore. See your dentist if your canker sores do not heal in a week or are painful.

Cold sores, also called fever blisters, are found outside the mouth and often erupt around the lips and sometimes under the nose or around the chin. They are caused by the herpes simplex virus type 1 and are very contagious. Once a person is infected with primary herpes, the virus stays in the body and causes occasional attacks. A dentist can prescribe antiviral drugs to help speed up healing.

Other types of common mouth sores are leukoplakia and candidiasis.

Leukoplakia are thick whitish-color patches that form on the inside of the cheeks, gums or tongue. These patches are caused by excess cell growth and are common among tobacco users. In some cases, they can result from irritations such as ill-fitting dentures or bridges or from chewing on the inside of the cheek, but they are sometimes associated with oral cancer. Your dentist may recommend a biopsy if the patch appears threatening. The biopsy will determine if the cells are cancerous. The most important aspect of treatment begins with removing the factors that contribute to the lesion: quitting tobacco or replacing ill-fitting dentures or bridges.

Candidiasis is a fungal infection that is also called moniliasis or oral thrushand is common among denture wearers. It most often occurs in people who are very young, elderly, and/or who have a problem with their immune system. People who have dry mouth syndrome are very susceptible to candidiasis. Candida may flourish after antibiotic treatment, which can decrease normal bacteria in the mouth. If you suffer from candidiasis, good oral hygiene is essential. If you wear dentures, always make sure to clean them thoroughly and remove them at bedtime. Saliva substitutes and prescription medications may be helpful when the underlying cause of dry mouth is incurable or unavoidable.

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Keep your smile bright!

Mouth sores and infections can improve your smile but it’s important to protect it with frequent brushing. Try one of our toothpastes to help keep your smile safe.