What is canker sore

Canker sores, also called aphthous ulcers, are small, shallow round lesions that develop on the soft tissues in your mouth, under your tongue, on the inside of your cheek, in the back of your throat or at the base of your gums ¹⁾. Canker sores can have a red edge and a gray center. They can be quite painful. They are not the same as cold sores, which are caused by herpes simplex. Furthermore, unlike cold sores, canker sores don’t occur on the surface of your lips and they aren’t contagious. They can be painful, however, and can make eating and talking difficult.

Canker sores may happen if you have a viral infection. They may also be triggered by stress, food allergies, lack of vitamins and minerals, hormonal changes or menstrual periods. In some cases the cause is unknown. Most canker sores go away on their own in a week or two. Check with your doctor or dentist if you have unusually large or painful canker sores or canker sores that don’t seem to heal.

Anyone can get canker sores, but people in their teens and 20s get them more often. They are more common in women than men.

Some conditions that can mimic canker sores include traumatic injury, autoimmune conditions, viral infections (such as herpes simplex “cold sores” and herpes zoster “shingles”), and most importantly, oral cancer. In addition, oral ulcers can be associated with a number of systemic conditions in which the oral ulcers represent only a small part of the underlying problem. A general rule of thumb recommended by health care professionals is that any ulcer that lasts for more than 10 to 14 days should be evaluated by a doctor and biopsied if necessary. Professionals trained in oral medicine have expertise in the diagnosis of such lesions.

Is there a cure for canker sores ?

Not yet. However, therapies are available to decrease pain, shorten the time of the ulcers, and even reduce how often they occur. These range from creams applied to the sores to stronger systemic medications.

Figure 1. Canker sore

Symptoms of canker sores

Most canker sores are round or oval with a white or yellow center and a red border. They form inside your mouth — on or under your tongue, inside your cheeks or lips, at the base of your gums, or on your soft palate. You might notice a tingling or burning sensation a day or two before the sores actually appear.

The discomfort and severity of canker sores can roughly be categorized as mild, moderate, or severe. Mild disease is characterized by its infrequent occurrence, short duration, and lack of severe symptoms. Fortunately, most patients who experience canker sores experience mild disease. While there is no formal classification to distinguish between moderate and severe disease, the presence of four or more canker sores per year with annoying but non-debilitating symptoms can be classified as moderate disease. Severe canker sores are often more widespread, more painful, and interfere with the patient’s ability to eat and speak. Unfortunately, individuals with severe disease often suffer frequent to constant recurrence.

Most of the time, canker sores are self-limiting. This means that they will go away even without treatment.

There are several types of canker sores, including minor, major and herpetiform sores.

Minor canker sores

Minor canker sores are the most common and affects more than 80% of canker sore sufferers:

• Are usually small (less than 1 centimeter in diameter)
• Are oval shaped with a red edge
• Heal without scarring in one to two weeks

Major canker sores

Major canker sores are more severe and affects approximately 15% of patients with canker sores:

• Are larger (typically over 1 centimeter in diameter) and deeper than minor canker sores
• Are usually round with defined borders, but may have irregular edges when very large
• Can be extremely painful
• May take up to six weeks to heal and can leave extensive scarring

Herpetiform canker sores

Herpetiform canker sores are uncommon (occurring in less than 5% of people with canker sores) and usually develop later in life, but they’re not caused by herpes virus infection. These canker sores:

• Are pinpoint size
• Often occur in clusters of 10 to 100 sores, but may merge into one large ulcer
• Have irregular edges
• Heal without scarring in one to two weeks

When to see a doctor

Consult your doctor if you experience:

• Unusually large canker sores
• Recurring sores, with new ones developing before old ones heal, or frequent outbreaks
• Persistent sores, lasting two weeks or more
• Sores that extend into the lips themselves (vermilion border)
• Pain that you can’t control with self-care measures
• Extreme difficulty eating or drinking
• High fever along with canker sores

See your dentist if you have sharp tooth surfaces or dental appliances that seem to trigger the sores.

Causes of canker sore

The precise cause of canker sores remains unclear, though researchers suspect that a combination of factors contributes to outbreaks, even in the same person.

Possible triggers for canker sores include:

• A minor injury to your mouth from dental work, overzealous brushing, sports mishaps or an accidental cheek bite
• Toothpastes and mouth rinses containing sodium lauryl sulfate
• Food sensitivities, particularly to chocolate, coffee, strawberries, eggs, nuts, cheese, and spicy or acidic foods. Strategies for identifying potential allergens include observing any relationship between the intake of a particular food or beverages and development of canker sores.
• A diet lacking in vitamin B-12, zinc, folate (folic acid) or iron
• An allergic response to certain bacteria in your mouth
• Helicobacter pylori, the same bacteria that cause peptic ulcers
• Hormonal shifts during menstruation
• Emotional stress
• Two frequent food additives that are associated with canker sores are the spice cinnamon and benzoic acid (a common preservative found in foods and soft drinks). A trial elimination of a suspected food substance or additive is a sound approach to identifying potential allergens.

Canker sores may also occur because of certain conditions and diseases, such as:

• Celiac disease, a serious intestinal disorder caused by a sensitivity to gluten, a protein found in most grains
• Inflammatory bowel diseases, such as Crohn’s disease and ulcerative colitis
• Behcet’s disease, a rare disorder that causes inflammation throughout the body, including the mouth
• A faulty immune system that attacks healthy cells in your mouth instead of pathogens, such as viruses and bacteria
• HIV/AIDS, which suppresses the immune system

Unlike cold sores, canker sores are not associated with herpes virus infections.

Risk factors for canker sores

Anyone can develop canker sores. But they occur more often in teens and young adults, and they’re more common in females.

Often people with recurrent canker sores have a family history of the disorder. This may be due to heredity or to a shared factor in the environment, such as certain foods or allergens.

How To Prevent Canker Sores

Canker sores often recur, but you may be able to reduce their frequency by following these tips:

• Watch what you eat. Try to avoid foods that seem to irritate your mouth. These may include nuts, chips, pretzels, certain spices, salty foods and acidic fruits, such as pineapple, grapefruit and oranges. Avoid any foods to which you’re sensitive or allergic.
• Choose healthy foods. To help prevent nutritional deficiencies, eat plenty of fruits, vegetables and whole grains.
• Follow good oral hygiene habits. Regular brushing after meals and flossing once a day can keep your mouth clean and free of foods that might trigger a sore.
• Use a soft brush to help prevent irritation to delicate mouth tissues, and avoid toothpastes and mouth rinses that contain sodium lauryl sulfate.
• Protect your mouth. If you have braces or other dental appliances, ask your dentist about orthodontic waxes to cover sharp edges.
• Reduce your stress. If your canker sores seem to be related to stress, learn and use stress-reduction techniques, such as meditation and guided imagery.

How is a canker sore diagnosed ?

Tests aren’t needed to diagnose canker sores. Your doctor or dentist can identify them with a visual exam. In some cases, you may have tests to check for other health problems, especially if your canker sores are severe and ongoing.

Canker sore treatment

As with all disorders of the mouth, an accurate diagnosis by a trained healthcare professional is required before treatment is started. This is particularly important for canker sores, since several other conditions can cause ulcers in the mouth that may mimic typical canker sores.

Treatment usually isn’t necessary for minor canker sores, which tend to clear on their own in a week or two. But large, persistent or unusually painful sores often need medical care. A number of treatment options exist.

In general the goals of treatment are threefold: to decrease pain, speed healing, and prevent recurrence. Currently, no available therapy meets all these goals, although most therapies do provide some benefit to those affected.

Related health problems

If your canker sores relate to a more serious health problem, your doctor will treat the underlying condition.

Over-The-Counter (OTC) preparations for treatment of canker sores fall roughly into four categories:

1. Occlusives,
2. Anesthetics,
3. Cleansing agents / antiseptics,
4. and other.

OTC products often combine multiple categories in order to increase effectiveness.

Occlusives or emollients

Occlusives or emollients are protective coatings that block irritation of the ulcer and associated nerve endings by providing a surface covering that shields the site from mechanical irritation; stimulation from acidic, salty, or spicy foods; and temperature changes. These coating agents are pharmacologically inert substances. They generally provide relief as long as they are in place, but it can be difficult to keep them adherent for sustained periods. When protective coatings are combined with a therapeutic agent, a two-fold benefit is obtained. The occlusive prevents external stimulation of the wound site and also holds the therapeutic agent in place. Representative products in this category include Zilactin® and Zilactin®-B, Orabase®, and Orabase® Soothe-N-Seal™.

Anesthetics

Anesthetics provide symptomatic relief and are often combined with other agents. The most frequently used agent is benzocaine 5 – 20%. However, benzocaine is a known allergen and should not be used by patients with hypersensitivity. Many OTC anesthetic products are available.

Cleansing agents/ Antiseptics

Cleansing agents/ Antiseptics can cleanse the area and decrease the number of bacteria on the ulcer surface. Products that release oxygen can be used as cleansing agents. The foaming of the oxygen exerts a mechanical action that loosens debris and cleanses the wound. Products in this category include Amosan®, Cankaid®, Gly-Oxide®, Orajel®, and Peroxyl®. Hydrogen peroxide when obtained as a 3% solution should be diluted with equal amounts of water before application either directly to the ulcer or as a mouthrinse. Sodium bicarbonate, either as a solution (½ to 1 teaspoon in 4 ounces of water) or as a paste, can also be used to for wound cleansing.

Mouth rinses

If you have several canker sores, your doctor may prescribe a mouth rinse containing the steroid dexamethasone to reduce pain and inflammation or lidocaine to reduce pain.

Topical products

Over-the-counter and prescription products (pastes, creams, gels or liquids) may help relieve pain and speed healing if applied to individual sores as soon as they appear. Some products have active ingredients, such as:

• Benzocaine (Anbesol, Kank-A, Orabase, Zilactin-B)
• Fluocinonide (Lidex, Vanos)
• Hydrogen peroxide (Orajel Antiseptic Mouth Sore Rinse, Peroxyl)

There are many other topical products for canker sores, including those without active ingredients. Ask your doctor or dentist for advice on which may work best for you.

Oral medications

Oral medications may be used when canker sores are severe or do not respond to topical treatments. These may include:

• Medications not intended specifically for canker sore treatment, such as the intestinal ulcer treatment sucralfate (Carafate) used as a coating agent and colchicine, which is normally used to treat gout.
• Oral steroid medications when severe canker sores don’t respond to other treatments. But because of serious side effects, they’re usually a last resort.

Cautery of sores

During cautery, an instrument or chemical substance is used to burn, sear or destroy tissue.

Debacterol is a topical solution designed to treat canker sores and gum problems. By chemically cauterizing canker sores, this medication may reduce healing time to about a week.

Silver nitrate — another option for chemical cautery of canker sores — hasn’t been shown to speed healing, but it may help relieve canker sore pain.

Canker sore home remedies

Nutritional supplements

Your doctor may prescribe a nutritional supplement if you consume low amounts of important nutrients, such as folate (folic acid), vitamin B-6, vitamin B-12 or zinc.

To help relieve pain and speed healing, consider these tips:

• Rinse your mouth. Use salt water or baking soda rinse (dissolve 1 teaspoon of baking soda in 1/2 cup warm water).
• Dab a small amount of milk of magnesia on your canker sore a few times a day.
• Avoid abrasive, acidic or spicy foods that can cause further irritation and pain.
• Apply ice to your canker sores by allowing ice chips to slowly dissolve over the sores.
• Brush your teeth gently, using a soft brush and foaming-agent-free toothpaste such as Biotene or Sensodyne ProNamel.
• Canker sore toothpastes lack a detergent known as SLS (sodium lauryl sulfate). In some patients, using an SLS free toothpaste reduces the frequency of outbreaks.