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Understanding Canker Sores

Canker sores are often painful and irritating lesions that appear inside, and on the areas surrounding, the mouth. If you have a tendency to develop these sores, then you know how frustrating they can be. The main goal when you have a canker sore is to be rid of it as quickly as possible. To do that, it helps to know more about these sores and what causes them.

What Are Canker Sores?

The technical name for canker sores is aphthous ulcers. They are small lesions that appear inside your mouth as round or oval sores. They usually have a red border and a yellow or white center, appearing in a variety of sizes. Canker sores are not generally dangerous as they are benign and not contagious. Were you to kiss someone who had a canker sore, you wouldn't have to worry about "catching" it. However, secondary infections can occasionally develop.

What Causes Canker Sores?

People who regularly experience canker sores may notice that the issue arises as a result of different causal factors. For instance, you may know that you tend to get canker sores if you bite your lip or feel stressed. These are known as "triggers" and, originating stimuli which vary between individuals. Regardless of personal triggers, the exact cause of canker sores is unknown. Most likely, aphthous ulcers are caused by a number of different factors working together. For some people, canker sores could be linked to an auto-immune response.

Where Do Canker Sores Typically Develop?

Typically, these little ulcers develop inside the mouth, where any soft tissue is subject to developing a canker sore. Usually, these sores will develop on the inside of your cheeks and lips, on your gums, and on the top and tip of the tongue. Cold sores can be easily confused with canker sores, however these are two different concerns. Canker sores will never develop on your lips or the outside of your mouth.

What Are the Symptoms of Canker Sores?

The most common symptom of canker sores is localized pain. Sometimes, before a sore develops, you'll know it's coming because of a burning, itching, or stinging sensation in the area where the sore will grow. Once the sore has developed, it will be painful to the touch, usually also hurting when the sore contacts food. Sometimes, even your own tongue can be painful for the sore to encounter. In severe cases, the pain can make it difficult for people to eat or drink.

How Long Do Canker Sores Last?

The sores themselves usually last between 7 and 10 days. You should call your dentist if you have:

  • Extremely large sores

  • Spreading sores

  • Sores that last longer than two weeks

Do Canker Sores Cause Other Symptoms?

Usually, there are no other symptoms in the body as a result of developing canker sores. That said, in rare cases, a person may develop a fever when they are getting a canker sore.

Will Canker Sores Keep Coming Back?

There is a condition called aphthous stomatitis which is characterized by the repeated development of canker sores. About 20% of the population is affected by aphthous stomatitis to some degree. This condition usually develops in childhood and goes away with age. Not all canker sores are caused by aphthous stomatitis. However, chances are, if your child gets a canker sore they will eventually get another one. There is no cure for aphthous stomatitis, but you can treat the canker sores that develop.

How Do You Treat Canker Sores?

The goal when treating canker sores is to reduce pain and promote healing. For most people, the sores are not painful enough to require any treatment at all. However, if you have a particularly painful ulcer, reducing the pain may be necessary to make it comfortable to do things like eat. Remedies for canker sores include:

  • Topical Anesthetics: Corticosteroid creams and oral pain reliever pastes are the first choice for treatment of canker sores. Products such as Oragel and Orabase are applied topically and will numb the pain.

  • Topical Antiseptics: Antibacterial rinses can be used to both speed up the healing time for canker sores, and prevent a secondary infection from occurring. Your doctor may prescribe an antibiotic rinse or an anti-inflammatory steroid mouthwash.

  • Oral Medications: Oral medications such as ibuprofen, naproxen, aspirin, and acetaminophen can be used for pain relief. They will also help with inflammation.

  • Zinc lozenges and Vitamin C may help with symptoms as well.

How Do You Prevent Canker Sores?

The best way to avoid canker sores is to avoid doing anything that triggers them for you. This can include:

  • Avoiding spicy or acidic foods

  • Using a soft-bristled toothbrush to lessen irritation

  • Using relaxation techniques to reduce stress

  • Being careful to avoid biting your lips, tongue, or cheeks

Canker sores are irritating and painful, but there are some things you can do to make them more tolerable. By gaining more information about them, you are better prepared to avoid them when possible and treat them if they’re unavoidable. If you are still concerned about canker sores, and how they affect your life, speak to your dentist at your next prevention visit.


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