An oral ulcer is a sore that emerges on the gums, lips, or inner cheeks of the mouth. An open sore may appear for several reasons, including a bacterial infection, a burn, an injury, or a more severe viral infection such as the herpes simplex virus.
Many types of oral ulcer can be treated at home with regular brushing, rinsing, and topical analgesics. Cold sores that are caused by herpes infections are typically treated with prescription or over-the-counter topical creams and antiviral medications. With treatment, most oral ulcers heal in less than two weeks, but especially prolific, long-lasting, or painful sores should be inspected by a physician.
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A canker sore is an oral ulcer that is not the result of a virus and is not contagious. This type of open sore is caused by irritation or infection of mouth tissue. A person may experience a canker sore if she accidentally bites her inner cheek, burns her tongue on a hot drink, or has an allergic reaction to food. Bacteria that build up in the mouth from food or as a result of poor oral hygiene may infect sensitive tissue, causing inflammation and eventually oral ulcer. Diseases that affect the immune system can also lead to mouth sores, such as HIV and Crohn's disease.
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Canker sores are usually small and only cause mild discomfort. Large lesions, however, can be painful and highly sensitive to food and drink. Most instances of minor canker sores go away on their own in about two weeks with regular brushing and rinsing. More severe oral ulcers, which can last for several months, are typically treated with topical medications that reduce inflammation and promote healing. Depending on the cause of major canker sores, a doctor may suggest vitamin supplements to boost the immune system or medications to treat underlying diseases.
A cold sore is a contagious oral ulcer that usually appears on the outer lip. A person usually notices a tingling sensation one to two days before a sore begins to physically appear. A red blister develops, breaks open, and tends to ooze clear or white pus. The blister crusts over as it begins to heal and usually disappears in about ten days without treatment. Since cold sores can be unsightly and uncomfortable, however, many people try to treat them immediately.
Over-the-counter topical creams may be used to dry out cold sore blisters and promote faster healing. People who suffer from frequent or severe outbreaks can seek specialized treatment and preventative information from their doctors. A physician might prescribe a high-strength topical medication or antiviral pills to boost the immune system and suppress herpes outbursts. The herpes simplex virus is incurable, and sufferers often experience outbreaks of cold sores sporadically throughout their lives.