Canker Sores Can Be Painful

By Premier Dental of Ohio

Chronic canker sores can be painful and irritating

Painful mouth sores and ulcers can cause significant disruption in your ability to eat and drink, and even speak sometimes.  One of the most common types of ulcers in the oral cavity is the canker sore.  If you or a loved one suffers from these, you know that they are tough to manage.  In this article, we will cover the essential information you need to know about these terrible ulcers.

What are Canker Sores?

Canker sores are recurring ulcerations in the mouth that we officially call aphthous ulcers.  These painful sores only occur on the areas of gum tissue not attached to underlying jawbone.  This means they do not happen on the roof of the mouth or the gums near the teeth.  They do occur pretty much everywhere else: the inside of the lips and cheeks, the tongue, the floor of the mouth, the soft palate and even the tonsils.

A typical canker sore is white to yellowish in color and has a red ring of inflammation surrounding it.  They do not bleed or swell.  The ulcers are flat and very painful.  There are three different categories of aphthous ulcers.

1. Minor Aphthous Ulcers

The most common type of canker sore is a minor aphthous ulcer.  This is an ulcer smaller than ten millimeters in diameter, which typically lasts seven to ten days.  

2. Major Aphthous Ulcers

A major aphthous ulcer is similar to the minor, but differing in its size and duration.  They tend to be significantly larger and can last up to six weeks.  Due to their larger size and longer duration, they cause quite a bit more pain than the minor ulcers.

3. Herpetiform Aphthous Ulcers

Herpetiform aphthae take their name from the oral sores caused by the Herpes Simplex Virus type 1 that they resemble.  Herpetiform aphthous ulcers occur in small clusters of multiple sores, just like HSV-1 lesions (typically called cold sores or fever blisters).  The difference between the two, and the distinguishing factor, is their locations.  HSV-1 does occur on the outside of the lips, the hard palate, or the attached gum tissues near teeth; these are the places inside the mouth that aphthous ulcers do not happen.  Your dentist can tell which of these clusters of sores you have simply by seeing where they occurred.

What Causes Canker Sores?

Officially, the cause of canker sores is unknown.  There are many suggestions in the scientific literature, but no single cause can be pinpointed.  People who suffer from canker sores usually know what their specific risk factors are.  We do know that there are several predisposing factors that can increase someone’s risk for developing aphthous ulcers.

Trauma to the Tissue

Many aphthous ulcer sufferers know that if they accidentally bite their lip, cheek or tongue, the likelihood of it become a canker sore is high.  The injury itself can lead to the development of the ulcer.  An uncomfortable complication with this cause of ulcers is that you are at risk for biting or injuring the area again, which can cause delayed healing and moderate to severe pain.


People with food allergies or allergies to chemicals in oral care products are likely to develop aphthous ulcers when their mouths are exposed to these allergens.  If you know you have particular allergies, you should avoid those items to prevent the formation of ulcers.  If you begin developing ulcers without explanation, you may need to seek medical attention to diagnose any potential new allergies.

Nutritional Deficiency

An important predisposing factor for aphthous ulcers is deficiencies in essential vitamins and minerals.  Studies link canker sores with deficiencies in Zinc among others.  A condition known as malabsorption, in which the body does not properly absorb nutrients from the GI tract, also increases the incidence of aphthous ulcers.

How Can I Prevent Canker Sores?

Because no one has pinpointed an exact cause, prevention can be tricky.  At this point, we advise our at-risk patients to focus on eliminating these predisposing factors.  This means anyone with a tendency to develop canker sores should work diligently to identify and avoid any potential allergens.  In general, you should also work with your medical doctor to ensure that you are achieving your optimal health through a healthy diet and exercise so that you can rule out any nutritional deficiencies.

Avoiding trauma is more difficult as no one means to bite his or her lips or tongue during chewing.  The best advice we can give to fight this risk factor is to chew more slowly and take smaller bites.  If this becomes a continual problem, you should consider consultation with an orthodontist to evaluate the position of the teeth.  Perhaps misalignment of the teeth is predisposing you to lip, cheek and tongue biting.

How Can I Relieve the Pain of Canker Sores?

You can find over-the-counter remedies for canker sores, and many of them do provide relief.  There are numbing agents, such as Anbesol and Orajel, and you should use these with caution.  When overused, they can damage the soft tissues and actually slow down the healing process.

Over-the-counter pain relievers, like Tylenol and Advil, can help, too.  Take them only as directed, and if they do not provide relief, stop taking them.

Colgate makes a mouthwash to reduce the pain of mouth sores called Peroxyl, and many people feel that it is effective.  You can also perform simple warm salt water rinses, which reduce inflammation and promote healing.  You can find the simplest and fastest pain relief by holding a small ice cube against the sore.  The cold reduces inflammation, and you may experience a minor numbing effect.

In order to prevent further irritation of the ulcer, you should avoid foods, drinks and oral care products that contain alcohol.  Stay away from acidic and carbonated beverages, and carefully monitor the temperature of food and drinks.  Very hot food or drink will be painful and irritate the healing sore.

How Can My Dentist Help with Canker Sores?

If you have a canker sore that persists or causes pain you are unable to manage, you should see your dentist.  Prolonged major aphthous ulcers may require prescription steroid treatment in order to promote healing.  Your dentist can prescribe soothing ointments or steroid creams to place directly on the ulcer, or a mouthwash that both provide pain relief and promote healing.

Some dentists are also able to offer a procedure using a dental laser to treat the canker sore.  The laser energy seals the ulcerated tissue, providing immediate pain relief.  It also reduces inflammation at the site and promotes faster healing.

More Questions about Chronic Canker Sores?

Call your nearest Premier Dental of Ohio location today to schedule a visit with one of our skilled dentists.  We can answer any question you have about canker sores, assess your specific problem area, and help alleviate your symptoms.

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