What Causes Canker Sores?


Canker sores can be a real pain in the mouth! They might not be very dangerous, but they can make it pretty hard to have a good day.

These angry little ulcers can form inside our lips and cheeks without warning and can take a few days to heal. Luckily, there’s a lot we can do to avoid getting them and help them heal faster when we do.

Avoidable Canker Sore Triggers

These are the top five causes of canker sores:

  • Dental/orthodontic appliances. Ill-fitting dentures can cause canker sores when they irritate the tissues of the mouth, and so can braces.
  • Acidic foods. Highly acidic foods like pineapples, lemons, strawberries, and tomatoes, as well as sour candies, can make you more vulnerable to canker sores.
  • Sickness. When we already have some type of infection, the chances go up to develop canker sores.
  • Stress. Stress can be pretty hard on the immune system, leaving the mouth more vulnerable to developing sores.
  • Tissue injury. We all bite our cheeks or lips from time to time, but when that happens, it’s easy for it to get temporarily worse because it swells up and we keep biting it!

Simple Canker Sore Remedies

Try to learn what your canker sore triggers are if you’re prone to getting them, because they’re easier to avoid once we know the cause. Cutting down on acidic foods is a great step. Using more dental wax can help if your braces are jabbing you in the cheek, or getting the problem spots checked by the orthodontist. Also consider exploring different ways of reducing stress so your immune system won’t be under as much strain.

If you’re doing all this and still getting sores, there are a few other things you can do:

  • Choose a soft-bristled toothbrush to minimize irritation. (Usually a good choice anyway.)
  • Brush with a toothpaste free of sodium laurel sulfate.
  • Rinse with warm saltwater to reduce inflammation and speed up healing. (Do not swallow.)
  • Apply a topical medication or take oral pain relief medication to reduce discomfort.

Prevent Canker Sores from Developing

Certain vitamins and minerals, such as vitamin B12, iron, and folate, are great for preventing canker sores, and we can get plenty of them by eating more yogurt, spinach, kale, parsley, carrots, and salmon. Keeping up with daily oral hygiene is also essential, because our mouths are healthier when we’re keeping the plaque under control.

Come to the Dentist with Your Questions

If you have any concerns about canker sores that we haven’t addressed here, the dentist can help! Schedule an appointment, even if it’s not the right time of year for one of your regular dental exams. It never hurts to get professional medical advice about an oral health issue!

We love and appreciate all our patients!

Top image used under CC0 Public Domain license. Image cropped and modified from original.
The content on this blog is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.