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Mouth ulcers — also known as canker sores — are normally small, painful lesions that develop in your mouth or at the base of your gums. They can make eating, drinking, and talking uncomfortable.
Women, adolescents, and people with a family history of mouth ulcers are at higher risk for developing mouth ulcers.
Mouth ulcers aren’t contagious and usually go away within one to two weeks. However, if you get a canker sore that is large or extremely painful, or if it lasts for a long time without healing, you should seek the advice of a doctor.
There is no definite cause behind mouth ulcers. However, certain factors and triggers have been identified. These include:
- minor mouth injury from dental work, hard brushing, sports injury, or accidental bite
- toothpastes and mouth rinses that contain sodium lauryl sulfate
- food sensitivities to acidic foods like strawberries, citrus, and pineapples, and other trigger foods like chocolate and coffee
- lack of essential vitamins, especially B-12, zinc, folate, and iron
- allergic response to mouth bacteria
- dental braces
- hormonal changes during menstruation
- emotional stress or lack of sleep
- bacterial, viral, or fungal infections
Mouth ulcers also can be a sign of conditions that are more serious and require medical treatment, such as:
- celiac disease (a condition in which the body is unable to tolerate gluten)
- inflammatory bowel disease
- diabetes mellitus
- Behcet’s disease (a condition that causes inflammation throughout the body)
- a malfunctioning immune system that causes your body to attack the healthy mouth cells instead of viruses and bacteria
There are three types of canker sores: minor, major, and herpetiform.
Minor canker sores are small oval or round ulcers that heal within one to two weeks with no scarring.
Major canker sores are larger and deeper than minor ones. They have irregular edges and can take up to six weeks to heal. Major mouth ulcers can result in long-term scarring.
Herpetiform canker sores are pinpoint size, occur in clusters of 10 to 100, and often affect adults. This type of mouth ulcer has irregular edges and will often heal without scarring within one to two weeks.
You should see a doctor if you develop any of the following:
- unusually large mouth ulcers
- new mouth ulcers before the old ones heal
- sores that persist more than three weeks
- sores that are painless
- mouth ulcers that extend to the lips
- pain that can’t be controlled with over-the-counter or natural medication
- severe problems eating and drinking
- high fever or diarrhea whenever the canker sores appear
Your doctor will be able to diagnose mouth ulcers through a visual exam. If you’re having frequent, severe mouth ulcers, you might be tested for other medical conditions.
Most mouth ulcers don’t need treatment. However, if you get mouth ulcers often or they’re extremely painful, a number of treatments can decrease pain and healing time. These include:
- using a rinse of saltwater and baking soda
- placing milk of magnesia on the mouth ulcer
- covering mouth ulcers with baking soda paste
- using over-the-counter benzocaine (topical anesthetic) products like Orajel or Anbesol
- applying ice to canker sores
- using a mouth rinse that contains a steroid to reduce pain and swelling
- using topical pastes
- placing damp tea bags on your mouth ulcer
- taking nutritional supplements like folic acid, vitamin B-6, vitamin B-12, and zinc
- trying natural remedies such as chamomile tea, echinacea, myrrh, and licorice root
You can take steps to reduce the occurrence of mouth ulcers. Avoiding foods that irritate your mouth can be helpful. That includes acidic fruits like pineapple, grapefruit, oranges, or lemon, as well as nuts, chips, or anything spicy.
Instead, choose whole grains and alkaline (nonacidic) fruits and vegetables. Eat a healthy, well-balanced diet and take a daily multivitamin.
Try to avoid talking while you’re chewing your food to reduce accidental bites. Reducing stress and maintaining good oral hygiene by using dental floss daily and brushing after meals also may help. Finally, get adequate sleep and rest. This not only will prevent mouth ulcers, but a host of other illnesses as well.
Some people find avoiding soft bristle toothbrushes and mouthwashes that contain sodium lauryl sulfate also helps. Your dentist can give you wax to cover dental or orthodontic mouth devices that have sharp edges.