Canker sores (not to be confused with cold sores) are small, shallow sores that form on the inside of your mouth or on your tongue. Often ringed in red with a white or yellow centre, they can be extremely painful depending on their location – especially when talking or eating. While not everyone experiences canker sores regularly, those who do know just how intrusive they can be.

There are many old wives’ tales about the causes, symptoms and treatments for canker sores, ranging from the plausible but untrue (they’re actually not contagious and caused by infection) to the outright outlandish (you really can’t get them by telling lies). Many incorrectly believe that canker sores are caused by oral herpes virus infections. One idea that’s still pervasive to this day is that canker sores are caused by putting dirty fingers in your mouth.  

Let’s set the record straight right here and now: Putting your fingers in your mouth – while not the most hygienic habit to have – does not cause canker sores. The origin of that rumour likely began with parents trying to stop their children from putting their hands in their mouths or sucking their thumbs. In fact, while the precise cause of canker sores is still unknown, there are many suspected factors that make you more at-risk to develop them, including:

• A family history of canker sores

• Stress or fatigue

• Food sensitivities, such as to spicy or acidic food

• A vitamin deficiency, such as low iron or vitamin B12

• Mouth trauma like a bit lip

• Intestinal issues like celiac disease, IBS or Crohn’s disease

Fortunately for most of those who suffer with canker sores, they typically heal on their own in around two weeks (though in some cases, major sores can take longer) without any specific treatment. You can, however, avoid triggering foods and make sure to drink a lot of cold, clear fluids. Regular saltwater rinses can also help with pain.  

If you have a canker sore that’s persisted for longer than a few weeks, it’s time to see your dentist! We can examine the area to make sure that nothing more serious is going on and make recommendations about how best to manage discomfort. We make booking an appointment easy – just use the orange “Book Online” button to get started!

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