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The Complete Guide to Mouth Ulcer Symptoms and Treatment

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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 they can occur in 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

A canker sore is a round mouth ulcer. These ulcers are usually white or yellow with red borders. 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.

Symptoms sometimes begin before the canker sore appears. Some people first notice a tingling or burning sensation, followed by a canker sore a few days later.

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 typically appear on the surface of the lips, although they can also occur around the nose or under the chin. 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 sore. They are usually smaller than 1 centimetre in diameter. These sores heal within a week or two and cause no 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 centimetre 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. 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 don't cause scarring.

The Causes of Canker Sores

The exact cause of canker sores is still unknown. One theory is that oral ulcers appear when the body's white blood cells attack the cells that line the inside of the mouth due to an immune system malfunction. Since people with recurring canker sores often have family members with the same condition, the sores may also be hereditary, explains the Mayo Clinic. The family connection could also be explained by shared environmental factors rather than genes, however, so more research is needed in this area.

Dentistry IQ notes that canker sores are associated with nutritional deficiencies, especially in children. A lack of vitamin B12 or a specific nutrient, such as calcium, folic acid or zinc, may cause or worsen an ulcerous outbreak.

Researchers think multiple factors may be at play in a canker sore outbreak. These factors could include a combination of environmental triggers and certain health conditions.

Potential Triggers

There are many potential triggers of canker sores. In some cases, they can 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. A canker sore can also be triggered 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 can also be triggered by food sensitivities, with the main offenders being chocolate, coffee and citrus fruits, the Cleveland Clinic explains. Spicy or acidic foods may also irritate the oral tissues, which could lead to sores.

Sodium lauryl sulfate (SLS) is another potential cause of canker sores. SLS is a foaming agent used in many toothpastes, cosmetics and cleaners. According to Environmental Health Insights, this ingredient doesn't pose a threat to human health when it's properly formulated. While the ingredient is considered safe, it can increase irritation inside the mouth if you have mouth ulcers.

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 is not yet 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 affect oral health, especially in women. Moreover, 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.

Associated Conditions

Some systemic health conditions may cause a higher instance of canker sores. Your doctor or dentist can advise you on possible connections between canker sores and your other health conditions.

The group of digestive problems known as inflammatory bowel disease (IBD) is associated with aphthous ulcers. Crohn's disease and ulcerative colitis, which cause inflammation in the digestive tract, can also result in mouth sores. The gastrointestinal effects of celiac disease make it another one of the many conditions associated with canker sores. People with celiac disease have a sensitivity to gluten, a protein that's found in wheat, rye, barley and other grains, and their inability to absorb this protein may result in oral problems.

Diseases that attack the immune system often cause aphthous ulcers, as well. People living with HIV frequently develop canker sores and other oral health problems as a result of being immunocompromised. In addition, difficulty eating and talking on account of ulcers can make it hard to take medication and stay well-nourished.

Lupus and Behcet's Disease are also conditions that can be linked to canker sores. A rare autoimmune condition, Behcet's Disease causes inflammation throughout the body, according to the American Behcet's Disease Association. It can also affect the mouth. If you are HIV-positive or immunocompromised, talk to your dentist about managing oral pain and sores.

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 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. Yoghurt, 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.

Dietary changes aren't the only way to ease the discomfort associated with these ulcers: ice is another easy home remedy to try when you have painful canker sores. The Mayo Clinic recommends letting ice chips slowly melt against the sores to help relieve pain and swelling.

Rinsing your mouth with a salt water or baking soda rinse may help speed up healing and relieve pain. To make a salt water rinse, combine one-half teaspoon of salt with one cup of warm water. If you'd prefer a baking soda rinse, simply mix one teaspoon of baking soda into half a cup of warm water.

Licorice root may also be helpful. According to the University of Michigan, chewing licorice supplements (not the candy!) may speed recovery time for stubborn canker sores.

Over-the-Counter Solutions

Home remedies aren't the only treatment option for canker sores. There are also many over-the-counter products available. These products can be purchased from pharmacies or grocery stores without a prescription, and they could help control pain or speed up healing.

Some products come in the forms of pastes, gels or creams, and they're applied directly to the canker sores. Other products come in liquid form, such as mouth rinses. Since so many products are available, it can be hard to make a selection. Ask your pharmacist or dentist to recommend an appropriate over-the-counter product for your canker sores, if one is needed.

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.

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. For example, if a nutritional deficiency is to blame, you may be prescribed a nutritional supplement. Ask your doctor for more details about the treatment plan for your condition, if you have one.

To treat canker sores one by one, your dentist may suggest a minor surgical procedure called cauterisation. This procedure involves chemically burning or destroying a targeted area of tissue with a specialised instrument. Cauterisation can reduce healing time or relieve pain, depending on the chemical being used.

Tips for Preventing Canker Sores

Canker sores are uncomfortable; 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, Delta Dental recommends keeping 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 a day will help keep your teeth and gums healthy, but surprisingly, they also help prevent canker sores from forming. A good oral hygiene routine ensures food doesn't remain 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, writes the NHS. 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 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.

The Cleveland Clinic explains that canker sores can occur three or four times per year. However, some people experience canker sores more frequently, which can be cause for concern. If you have frequent outbreaks of canker sores, or if new canker sores are developing before the old ones get a chance to heal, see your doctor.

Mouth ulcers are a common oral health concern; they usually go away on their own fairly quickly. In some cases, however, they can indicate a more serious condition. If you're concerned about ulcers inside your mouth, don't hesitate to see your doctor or dentist.

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