What Are Canker Sores and How to Prevent Them

Dental Health
By: Spirit Dental
June 7, 2021

A woman drinking coffee at a coffee shop

If you’ve ever had a canker sore, you know how annoying and painful they can be. But what exactly are they, what causes them, and are there any ways to prevent them? Keep reading to learn all about this common oral health ailment. 

What Are Canker Sores?

Canker sores are ulcers or lesions that are described as shallow, small, and oval or round. In terms of their color, they’ll typically be white, yellow, or gray, and there’s also some redness surrounding the sore. 

These sores develop in the mouth, such as on the inside of the lips or cheeks, at the base of the gums, on the soft palate, and on the tongue. The good news is these sores aren’t contagious, and they generally heal on their own. But while you have them, they can be painful to the point that you have trouble talking or chewing. 

Note: Minor canker sores are often small and may heal in a week or two, while major canker sores are bigger and may take several weeks to heal.  

What Causes a Canker Sore?

Experts aren’t really sure what causes canker sores, but certain things might trigger their development. Here are some examples:

  • Stress
  • Hormonal changes
  • Mouth injury (this might be caused by brushing too hard or by accidentally biting the inside of your cheek, as a couple examples)
  • Acidic or spicy foods, or any foods that you’re sensitive to
  • A lack of adequate zinc, iron, folate, or vitamin B12
  • Irritation caused by sodium lauryl sulfate, an ingredient commonly found in toothpaste and mouthwash
  • Irritation caused by braces, dentures, or other dental appliances

Other interesting things to keep in mind about canker sores:

  • If people in your family get canker sores often, you might too. 
  • Certain conditions, such as IBD and celiac disease, might cause canker sores. 
  • These sores aren’t caused by the herpes virus. 

How Can You Treat a Canker Sore?

Though they can cause quite a bit of discomfort, you don’t necessarily need to do anything to treat a canker sore, as it usually goes away on its own. 

However, if you want to get some relief, you can try over-the-counter products like Orajel. You can also consult your doctor or dentist to discuss options like prescription mouthwashes if you have a large canker sore that’s causing a lot of pain.    

In addition to avoiding triggers like acidic foods and beverages that could make the discomfort worse, you can also try rinsing your mouth with a mixture of water and baking soda or water and hydrogen peroxide. And it’s also wise to brush your teeth as gently as possible to avoid further irritation.   

Note: If your symptoms are severe, your sore is really big or isn’t healing, you have a lot of sores that keep coming back, or you have other symptoms (e.g. fever), it’s best to talk to your doctor to figure out how to tackle the problem. 

Can You Prevent Canker Sores?

Here are some simple steps you can take to help prevent the occurrence of unpleasant canker sores:

  • To avoid irritating your mouth, use a soft-bristled toothbrush to thoroughly and gently clean your teeth. And don’t forget to brush and floss daily!

  • Because chewing on gum might cause irritation, avoiding it may be helpful when it comes to preventing canker sores.

  • Test things out to see if you can figure out your triggers. Do you tend to get canker sores after eating a lot of spicy food? Or, you might try switching to products that don’t contain sodium lauryl sulfate (SLS) to see if that’s the irritant you need to avoid.

  • Eat a balanced diet, and take supplements if necessary, to ensure you aren’t deficient in any key nutrients. And practice stress-relieving techniques to keep your mind in a balanced and positive state as well. 

Can a Dentist Help If You Have Canker Sores?

Yes! Your dentist might be able to give you valuable tips about what to do to treat and prevent canker sores. Also, if your canker sores are caused by a dental appliance that needs to be adjusted, or by one or more teeth that have sharp surfaces, your dentist can fix those problems for you. Just more great reasons to have a high-quality dental plan in place!

So, to summarize: you generally don’t need to be too worried about canker sores, but don’t hesitate to see your dentist if they’re causing a lot of pain or aren’t healing properly. 






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