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Canker Sores: Causes and Treatments

Aphthous ulcers, more commonly known as Canker Sores, can be uncomfortable and hard to deal with. The term Aphthous ulcers comes from the Greek word aphthae which means “to set on fire” or “inflame.” Those who suffer from these ulcers know that description is fitting.

What Causes Aphthous ulcers?

The short answer is: we don’t know. However over the years a few possible causes emerged.

Local oral factors

These factors include trauma to the area and salivary gland dysfunction.

Microbiological factors

Some bacteria and viruses have been implicated. In fact it is thought, that after there is a trauma in the mouth, the bacteria in the mouth are presented to the immune system. The immune system then responds creating the aphthous ulcer.

Nutritional and allergic factors

Some vitamin deficiencies and food allergies have been implicated.

Research shows that sodium lauryl sulfate, a product found, in some toothpastes can be the cause of the ulcers.

Systemic conditions

A list of systemic conditions can present and manifest as ulcers in the mouth including diseases such as Behcet’s disease, Crohn’s disease, Celiac Disease, cyclic neutropenia, HIV/AIDS, MAGIC syndrome, and more.

Genetic/immunological factors

Finally, are there people that have defective local T-cell (a kind of immune cell) regulation and other immunologic issues that put them at risk for developing these ulcers

In short, it’s complicated.

Managing and treating

A good dentist will do some investigative work to try to really understand what’s behind a bad case of recurring aphthous ulcers. A dentist might want to know the history of the disease—how often it occurs, where it occurs, and how long it takes to heal. The dentist might also like to know if the person experiencing the ulcers have a medical history for any diseases. The dentist would also like to know if there is an important nutritional history or dental history.

No Treatment: Most cases do not need any treatment and go away automatically. If the cases are slightly more severe, more steps can be taken.

Sodium Lauryl Sulfate-Free Toothpaste: If aphthous ulcers bother you often, it might be a good idea to get some toothpaste without sodium lauryl sulfate since these can cause ulcers, as we have already learned.

Remove any obvious causes: Sometimes a sharp tooth or filling may cause trauma to in the mouth. A dentist can smoothen that tooth or filling to help your mouth heal properly.

Topical Therapy: Some are over the counter while others have to prescribed.

  • Topical therapies such as topical anesthetic like benzocaine (orajel®) can help relieve pain.

  • There are also surface protective bioadhesives that go on top of the canker sore to protect it.

  • In addition, early on in the stage of the ulcer, anti-inflammatory gels such as corticosteroids (Kenalog orabase) can be helpful.

  • Finally, a chemical cautery agent such as debactoral® can be used for immediate relief. The debacterol cautery hurts a lot for a few seconds and then you will feel much better.

Go see a dentist if you have more questions!

Source: Ship JA et al. Quintessence International 2000;31(2):95-112.

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