What is a canker sore?

A canker sore, also known as a mouth ulcers are small, round blister-like lesions that can erupt in many places inside your mouth like the cheeks, the base of the gums, tongue, and even the roof of the mouth. These sores can emulate a burning or tingling sensation in the mouth and make it difficult for you to eat or talk. Canker sores can easily be confused with cold sores or fever blisters, but they are clinically very different. While canker sores are non-contagious and normally occur inside the mouth, cold sores are caused by herpes simplex virus, typically appearing on the surface of the lips. They are also dangerously contagious!

According to the International Association of Oral and Maxillofacial Surgeons, an estimated 1 in every 5 people have experienced recurrent canker sores. These ulcerated lesions, though irritating and tender are inherently harmless.

Possible causes of canker sores

According to the American Dental Association (ADA), the exact cause of canker sores is uncertain but some experts believe that weakened immune system, harmful bacteria or virulent viruses may be involved. As noted by a number of studies, canker sores do exhibit a genetic predisposition to them.

Although a definitive cause cannot be pointed out, several trigger factors may be responsible for the development of canker sores in the mouth. According to Dentistry IQ, some of the potential risk factors that may make people susceptible to canker sores are:

• Mouth injuries due to dental work brushing, contact sports
• Food sensitivities to chocolate, coffee, highly acidic, or spicy foods
• Lack of micronutrients like iron, B12, zinc, and folic acid
• Immuno-suppressive or immune compromising medical conditions
• Psychological factors like excessive stress

In addition to these, sufficient researches have shown that toothpaste containing sodium lauryl sulfate (SLS), an anionic detergent, may be responsible for aggravating an ulcerous outbreak. Canker sores usually heal on their own after one or two weeks.

Can your toothpaste cause canker sores?

Many brands of commercially available toothpaste contain an ingredient called Sodium Lauryl Sulfate (SLS). SLS is a synthetic detergent and foaming agent, commonly used in household soaps, detergents, emulsifiers, surfactants, toothpaste, and mouth rinses. It gives you the bubbly, foamy feeling when you are brushing and automatically instils in your mind that the toothpaste is working. In contradicting evidence, when it comes to efficiency, it does not matter whether or not your toothpaste foams, instead SLS can be detrimental to your oral wellbeing.

Researchers affirm that SLS irritates the soft and sensitive tissues inside your mouth, removing the protective top lining tissues. This makes the function of these protective barriers obsolete and makes you susceptible to canker sores. Additionally, SLS is also a denaturant, which means that it can cause proteins in our tissues to denature, worsening ulcers that have already exposed underlying tissue layers inside the mouth.

A clinical trial was conducted by Norwegian researcherson the effect SLS had on 10 patients with multiple minor ulcers. It demonstrated that upon using a toothpaste containing 1.2% of SLS for three months, the participants had 14.3 ulcers on average. When they used SLS-free toothpaste for the next three months, they found participants with only 5.1 ulcers on average, clearly suggesting that the detergent was contributing to the development of ulcers. While many studies echoed these results, a 2012 study also highlighted that using an SLS-free toothpaste by those who already had a canker sore decreased the duration and pain of the ulcers.

Commercial names for SLS

With the ballooning awareness of the effects of SLS-containing toothpaste on the oral cavity, manufacturers have become creative with their SLS marketing strategies. When you look for SLS on the label of toothpaste tubes, you should also beware of the other sneakier names these ingredients could be marketed under. The EWG Cosmetics Database informs that SLS could be under different names like:

• Monododecyl ester sodium salt sulfuric acid
• Sodium Dodecyl sulfate
• Sodium dodecyl sulphate
• Sodium salt sulfuric acid
• Monododecyl ester
• Sulfuric acid monododecyl ester sodium salt
• Sulfuric acid
• Monododecyl ester
• Sodium salt
• A13-00356
• Akyposal SDS
• Aquarex Methyl

How to prevent or lessen canker sores?

Canker sores can be prevented by taking the following precautions:

• Avoid SLS toothpaste and mouthwash
• Avoid abrasive, spicy, or acidic foods that can cause further irritation
• Avoid tobacco
• Brush with a soft-bristled toothbrush and floss daily
• Use over-the-counter topical anaesthetics
• Make use of anti-microbial mouthwashes for temporary relief
• Use an SLS-free toothpaste or mouthwash, like St Andrews Trust dry mouth toothpaste or mouthwash for immediate relief and prevention of future canker sores
• Your dentist may also prescribe you antibiotics for recurrent canker sore infestations

You should visit your dentist if you are showing signs such as rapidly spreading sores, sores that last three weeks or longer, intolerable pain despite taking over the counter pain medication, and a high fever with the appearance of canker sores. Switch to SLS-free toothpaste, like St Andrews Trust dry mouth toothpaste to mitigate the risk of canker sores.