canker sores

The severe pain of a canker sore sends many sufferers searching for information about what they are and how you can manage them. Some people experience rare sores only once every few years, and others have them repeatedly for most of their lives. There is a lot of variance among canker sores, but the one commonality is that they hurt.

In this article, we will explain what you need to know about canker sores, and what you can do when you experience one.

What are Canker Sores?
“Canker sore” is an unofficial term for the oral soft tissue lesion known as aphthous ulcers. Some doctors or dentists will also call these by the plural aphthae. These sores always include an area of ulceration (or loss of superficial tissue layer) that is off-white to yellowish in color. A bright red ring of inflammation surrounds the ulcerated portion.
Canker sores vary widely in size, and they occur in specific areas of the mouth. Your dentist will classify your aphthous ulcer into one of three categories.

defend your teeth against the daily grind graphic

Different Types of Aphthous Ulcers

• Minor Aphthous Ulcer – Minor aphthous ulcers are the most common type of canker sore. These small mouth ulcers are usually round or oval in shape, ranging from two to eight millimeters in diameter. They can last for ten to fourteen days and usually do not leave any scar behind. Minor aphthous ulcers make up about eighty percent of all canker sores.
• Major Aphthous Ulcers – While major aphthous ulcers are far less common, making up only about ten to fifteen percent of canker sores, they are impossible to miss. They are extremely large, over a centimeter in diameter, and they can last for eight weeks. These severe ulcers do have the potential to leave scars inside the mouth.
• Herpetiform Aphthous Ulcers – This unusual type of canker sore is also rare, comprising only five to ten percent of aphthous ulcers. They received the name “herpetiform” because they mimic the appearance of the mouth sores caused by the Herpes Simplex Virus type 1 (HSV-1). Herpetiform aphthae occur in clusters of smaller ulcers that typically last for ten to fourteen days, like minor aphthous ulcers. The ulcers can blend together into one large, irregularly shaped ulcer, which does make them more painful.

What Causes Canker Sores?
Doctors, dentists and researchers have not identified a single cause for aphthous ulcers. Instead, there seem to be a variety of predisposing factors, which increase the likelihood that someone will experience these painful sores. By working to manage these risk factors, you may be able to reduce the frequency of your ulcers.
People commonly experience the development of an aphthous ulcer at the site of an injury to the soft tissues of the mouth. This includes minor lip, cheek or tongue biting, as well as injury to the tissues when undergoing dental treatment. The bite or injection site itself is not an ulcer, but it can develop into an ulceration as the result of trauma to the delicate soft tissues of the lips, cheeks, and tongue.
Dry Mouth
Saliva is essential for lubrication of the inside of the mouth. This lubrication enables your lips, cheeks and tongue to smoothly move along the teeth without injury. In a dry mouth, the lack of saliva leads to sticking between the teeth and the tissues lining the mouth. The friction itself can cause an ulcer, or the lack of lubrication can lead to more frequent bites.
Nutritional Deficiencies
People with deficiencies in a few essential vitamins or minerals may also experience frequent canker sores. Studies have shown that those with deficiencies in iron, zinc, folic acid, as well as vitamins B3, B12 and C may be more prone to suffer from frequent aphthous ulcers.
GI Disorders
Doctors have also correlated a high frequency of recurring canker sores with certain gastrointestinal problems. Specifically, those who suffer from Celiac Disease and a condition known as malabsorption tend to develop more aphthous ulcers than those with healthy GI tracts. Most likely, the link is due to a nutritional deficiency that these GI disorders can cause.

How Can I Prevent Canker Sores?
If possible, it is always best to prevent canker sores. They are difficult to manage, and they truly can interfere with your quality of life when they occur. Here are some of the best ways to prevent these painful ulcers.

Protect against Trauma
A great majority of canker sores result from an initial injury to the soft tissues. If you find yourself frequently biting your cheeks, lips, or tongue during normal chewing or speaking function, you should speak with your dentist. You may have an issue with jagged or sharp areas on the teeth that need smoothing.
You may also need to protect the soft tissues by covering the teeth and providing a barrier between the teeth and cheeks, lips and tongue. These injuries that cause canker sores can remain irritated for weeks on end if you continue biting them and re-injuring the initial site. Protecting the soft tissues from re-injury is essential for healing.
You can order a custom-made tongue and cheek biting guard from Sentinel Lab here.

Manage Dry Mouth
As we described earlier, a dry mouth is more prone to canker sores. You must work diligently to manage dry mouth through a variety of tactics. First, you should drink plenty of plain water to fight dehydration. Your body cannot make an adequate amount of saliva if you are dehydrated.
Next, you should work to stimulate the natural production of saliva. You can do this through chewing sugar-free gum or using products like Xylimelts, which produce a sweet flavor over a sustained release period to continually stimulate saliva.
You can also use salivary replacement products to help moisturize and lubricate the inside of your mouth when it feels dry. Biotene dry mouth gel is an easy product to find over the counter.

See Your Medical Doctor for Evaluation and Treatment
Since a few of the risk factors for canker sores involve medical conditions like nutritional deficiencies and GI problems, you may need to see your medical doctor. Your doctor can run tests to identify any underlying health conditions that are predisposing you to recurrent canker sores. Your treatment may involve seeing a nutritionist and implementing dietary changes.

What Can I Do to Relieve the Pain of a Canker Sore?
What if you already have a canker sore?

Here are a couple of tactics that are helpful to relieve the pain of aphthous ulcers.

ice for canker sores

The simplest and fastest way to relieve pain from a canker sore is to hold a small piece of ice inside your mouth over the sore. This provides a soothing or numbing effect of the pain. The cold also reduces inflammation around the sore. Be careful not to do this constantly. The tissue needs time to be at its normal temperature, too. Limit the ice to fifteen minutes, and take at least fifteen minutes off between applications.

Avoid Acidic Foods and Drinks

Certain foods and drinks will aggravate the ulcer and cause a burning or stinging sensation. While the sore is an open wound, you should avoid any foods and beverages that are very hot in temperature or very low in pH (acidic). This includes carbonated drinks, fruit juices, tomato sauces, anything pickled, or items high in vinegar content.

Over-the-Counter Pain Relievers

Many people find relief from taking over-the-counter medications like Advil or Tylenol. Do NOT place these tablet medications directly onto the ulcer. This will harm the tissue and delay healing. Take the medication orally as directed on the packaging.

Limit Speaking and Chewing

The more you move your mouth, the more likely you are to injure or irritate the site of an ulcer. Limit chewing by implementing a soft diet while the ulcer is present. Try to limit speaking as much as possible. The less friction the sore undergoes, the faster it will heal.

Cover the Teeth

Wear a protective covering over the teeth, like Sentinel’s “Tongue and Cheek Biting Relief Guards” linked below. This removes the risk of re-injury and also protects against further friction.
Prescription Medication
In cases of major aphthous ulcers, some people require prescription medication. These may involve topical ointments you can place over the sore or a medicated mouthwash you can rinse. These prescriptions typically include a steroid to fight inflammation, an antibiotic to prevent infection, and a topical anesthetic to reduce the pain.

Dental Treatment

Some dentists offer treatment of canker sores with dental lasers. Lasers can quickly reduce inflammation and place a type of “seal” over the sore. This reduces pain and speeds up the healing process.
What is the Most Important Thing to Know about Canker Sores?
Canker sores are painful and difficult to manage. Those who suffer from them frequently should take steps to reduce their risk factors. See your dentist if your ulcers become unmanageable.

Sentinel Mouthguards is a digital company dedicated to bringing high-quality mouth guard, dental retainer and teeth whitening solutions to the mass market at an affordable price. You can learn more about what we do by visiting this website link:

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Dr. Lara Coseo

Dr. Lara Coseo, (DDS, FAGD) is a 2004 graduate of Baylor College of Dentistry in Dallas, Texas. Having practiced general dentistry for 13 years, Dr. Lara currently serves as an Associate Professor at Texas A&M College of Dentistry.

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author_Dr. Lara Coseo, DDS
Dr. Lara Coseo

Dr. Lara Coseo earned her Doctor of Dental Surgery degree from Baylor College of Dentistry in 2004, and she was awarded a Fellowship in the Academy of General Dentistry in 2014. Dr. Lara retired from private practice in 2017 after being diagnosed with Stargardt’s Disease, a degenerative retinal disease causing rapid central vision loss. Even though she is unable to perform invasive dentistry, she remains passionate about patient education and all aspects of general dentistry. She would love to help you build relationships with your patients through web content, blogging and social media.

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