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Do you get canker sores? Do you wish these painful mouth ulcers would go away forever? There is hope! This video explains not only WHY we get canker sores but HOW to prevent them from coming back. Join Michael Aranda for an informative episode of SciShow!
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Michael: So you're sitting there trying to eat your breakfast burrito, but this thing inside your lip hurts every time you take a bite. Then you go for a swig of orange juice and it stings so much that your eyes start to water.

That's life with a canker sore, technically called an aphthous ulcer. Once you have one, you're pretty much stuck with it for the next week or so. But there are some things you can do to try to prevent canker sores in the first place, and there are ways to make them hurt less and maybe even heal faster.

To be clear, we're not talking about cold sores here, the bumps you might get on your lips outside your mouth, those are caused by a viral infection. Instead the aphthous ulcer are basically little abrasions inside your mouth. They're often caused by something that irritates a spot like braces or dentures rubbing against your cheek, or acidic or spicy foods, but there are other factors involved too.

Studies have shown that when people are especially stressed, they tend to get more canker sores, possibly because the hormones your body releases when you're stressed can trigger inflammation. And nutritional deficiencies, like if you're not getting enough iron or vitamin b12, can thin the cell layers lining your mouth leading to more canker sores. And then there are the unlucky folks who have recurrent aphthous stomatitis, or RAS, which basically means that they have extra painful canker sores that keep reappearing.

Researchers aren't totally sure why people get RAS, but it might have to do with genetics or higher stress levels. So to try to prevent canker sores you can avoid spicy foods, and be careful with anything sharp or pokey in your mouth like braces.

But, there's no guarantee that you won't get one. Tnyway the good news is there are things dentists recommend trying to make a canker sore less painful while it heals. You can buy treatments with a chemical called benzocaine, which interacts with your nerve endings to numbness or so it doesn't hurt when you chew. You can also rinse your mouth with some diluted hydrogen peroxide which will burn like the Sun, but will kill off bacteria that might infect the canker sore and make it stick around longer. And prescription medications with a steroid called fluocinonide can make the canker sore heal faster and interact with your immune system to bring down swelling.

For tougher cases like RAS, doctors can prescribe stronger meds like other steroids or antibiotics. They come with stronger side effects, but have been shown to reduce the number of canker sores people get, and make the ones they do get less painful. So the next time you get one of these annoying, painful things just remember, there is hope.

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