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Canker sores, also called mouth ulcers or aphthous ulcers, are one of the most common oral health conditions. The New York Times reports that teenagers and young adults are more likely to develop mouth ulcers, but it can happen to people of any age. Here’s everything you need to know about the symptoms, causes, and treatments of these common sores.

Symptoms of Canker Sores

canker sore is a round mouth ulcer. Usually, these ulcers are white or yellow, and their borders are red. While the sores are shallow, they can be painful, especially when eating or talking.

These sores can form in many places inside the mouth. You may notice them on the insides of your cheeks or lips, on your gums, on the roof of your mouth, or even on your tongue.

Sometimes, symptoms can begin before the canker sore appears. Some people notice a tingling or burning sensation first, and then a few days later, a canker sore develops.

Canker sores can easily be confused with cold sores, though these two oral health conditions are very different. Cold sores are caused by the herpes simplex virus, and they typically appear on the surface of the lips. They can sometimes form around the nose or under the chin, as well. Canker sores, on the other hand, form on the tissues inside the mouth.

Types of Canker Sores

Surprisingly, there’s more than one type of canker sore. Each type of sore has different symptoms and outcomes, and some are more common than others.

  • Minor aphthous ulcers. These are the most common type of canker sores. These sores are small and are usually smaller than 1 centimeter (0.4 inches) in diameter. They heal within a week or two, and they don’t cause any scarring, reports the Mayo Clinic.
  • Major aphthous ulcers. These are a more severe type of canker sore, but fortunately, they’re not as common as the minor variety. The sores are usually larger than 1 centimeter in diameter. In addition to being wider, they can also be deeper than minor canker sores. Major sores can be very painful. When they heal, which can take six weeks or more, they can leave behind extensive scars.
  • Herpetiform ulcers. These uncommon ulcers affect very few people with canker sores. Despite their name, they’re not caused by the herpes virus. They’re made up of clusters of anywhere between 10 and 100 sores, explains the Mayo Clinic, and these clusters of small sores can sometimes merge into one large ulcer. Despite this, they usually heal in about a week, and they don’t cause scarring.

The Causes of Canker Sores

The exact cause of canker sores is still unknown. Researchers think that multiple factors may be involved in a person’s canker sore outbreaks. These factors could include a combination of environmental triggers and certain health conditions.

Potential Triggers

There are many potential triggers of canker sores. Sometimes, they may be prompted by something as simple as a minor injury to the oral tissues: brushing your teeth too aggressively, accidentally biting your cheek, or crunching on a sharp corn chip. It could also be caused by the sharp edge of a dental appliance (such as a denture) or a chipped or broken tooth rubbing against your oral tissues.

Canker sores may also be triggered by food sensitivities. While you can be sensitive to any food, the main offenders relating to canker sores are chocolate, coffee, and citrus fruits, the Cleveland Clinic explains. Spicy or acidic foods could also irritate the oral tissues, which may lead to sores.

Stress has been associated with many health conditions, so it’s no surprise that it’s also a suspected trigger for canker sores. The connection between stress and canker sores isn’t well understood. One theory is that people who are stressed may be more likely to bite the insides of their cheeks, and this trauma can then lead to canker sores.

Some potential causes are outside of your control. Hormones have an effect on oral health, especially for women, and oral health problems may be connected to the monthly menstrual cycle, explains the Cleveland Clinic. Some women develop canker sores due to these hormonal changes. Other oral health problems, like swollen gums, bleeding gums, or swollen salivary glands can also be affected by changing hormones.

Home Remedies

The good news about mouth ulcers is that they typically go away on their own within one to two weeks, writes the National Health Service (NHS). A few home care tips may help ease the discomfort during the healing process.

While your canker sores are healing, try to avoid any foods or drinks that could further irritate them. Some of the foods and drinks to consider avoiding are:

  • Crunchy foods, like chips or toast
  • Acidic fruits, like citrus or tomatoes
  • Salty crackers or pretzels
  • Spicy foods or hot peppers
  • Very hot drinks, like tea or coffee

While many foods can irritate canker sores, don’t worry — there’s still plenty you can eat! Instead of irritating foods, opt for soft, bland foods. Yogurt, mashed potatoes, and pudding are just a few examples. Your dentist or doctor may be able to recommend other suitable foods to eat during this time.

Rinsing your mouth with salt water may help speed healing and relieve pain. To make a salt water rinse, combine one-half teaspoon of salt with one cup of warm water.

Professional Help for Mouth Ulcers

Some stubborn canker sores aren’t helped by home remedies or over-the-counter solutions. In these cases, your doctor and dentist can explore other options.

Prescription medications are one of the treatments your health professional may recommend. For example, prescription mouthwashes that contain steroids may be used to reduce the inflammation of canker sores.

If your dentist determines your canker sores are being triggered by a dental issue, that issue will need to be corrected. If the sharp edges of a broken tooth are rubbing against your oral tissues, your dentist may recommend an appropriate restoration. If your oral appliances are causing friction, your dentist may adjust them to reduce the problem.

If your doctor determines that an underlying health condition is connected to your canker sores, they may decide to focus on treating the systemic problem first. Since so many conditions can be connected to canker sores, treatments can vary significantly.

Tips for Preventing Canker Sores

Canker sores are uncomfortable, and once you’ve had one, you definitely won’t want another. Fortunately, there are many preventative measures you can use to help ward off future ulcers.

Avoiding triggers is an important method of preventing canker sores. If you’re not sure what’s causing your sores, it may be beneficial to keep an ulcer diary. By recording details about your canker sore outbreaks, you and your dentist can spot potential triggers more easily. For example, you might notice that you often develop canker sores after eating specific foods. With that knowledge, those foods can then be reduced or eliminated.

Brushing your teeth twice a day and flossing once per day keep your teeth and gums healthy, but surprisingly, they also help prevent canker sores from forming. A good oral hygiene routine ensures food isn’t remaining in your mouth where it could cause a sore.

Other healthy habits can help, too. Focus on eating a wide variety of healthy foods to ensure your body gets the nutrition it needs. Learn healthy ways to deal with your stress, and try to get enough sleep every night.

When to See a Doctor or Dentist

A mouth ulcer is rarely a sign of a serious health concern. However, there are some situations where seeing a doctor or dentist is recommended.

A canker sore that hasn’t healed within three weeks should be examined by a dentist or doctor, writes the Cleveland Clinic. Getting stubborn mouth ulcers examined is important because oral cancer can sometimes look like a harmless canker sore. When dentists think an ulcer in the mouth looks suspicious, they may perform a biopsy of the tissue.

If the symptoms associated with your canker sores are severe, consult your doctor. Some worrying symptoms could include a high fever or pain that can’t be managed at home. If the discomfort from your canker sores is making it very hard for you to eat or drink, you should also see your doctor.

Mouth ulcers are a common oral health concern, and usually, they go away on their own fairly quickly. Sometimes, they can be a sign of something more serious. If you’re concerned about ulcers inside your mouth, don’t hesitate to see your doctor or dentist.