How can you tell if a canker sore is healing

Canker sores are painful blisters that form inside of the mouth. These blisters can form on the tongue, throat, inner cheeks and gums in varying sizes. The exact reason for the formation of canker sores is unknown, however, there are a few different things that are known to attribute to the formation of the sores. Simple sores are formed when the tissue inside of the mouth is irritated or the body has been under a great deal of stress. Certain acidic foods may also cause the sores, but are more likely to irritate them. These foods include many different fruits with a sour taste, such as lemons. More complex canker sores may occur when a person has an immune system disorder, nutritional imbalances and certain diseases.

Table of Contents Show

Minor canker sores
Major canker sores
Herpetiform canker sores
When to see a doctor
From Mayo Clinic to your inbox
Risk factors
What color are canker sores when they are healing?
Do canker sores hurt more when healing?
Why do canker sores turn white?
How do you know when a canker sore is getting worse?

The symptoms of a canker sore include a swollen, painful blister that is located anywhere inside the mouth. Unlike cold sores, canker sores only occur within the mouth and are often white, grey or pinkish red in appearance. Prior to the sore appearing within the mouth, a burning or tingling sensation may occur in the affected area. When the case of a sore is more severe, there may be more serious symptoms such as; fever, fatigue and swelling of the lymph nodes.

Simple canker sores will often heal on their own within a couple of days. As the sores begin to heal, the pain will also begin to lessen until it has subsided. If the sore starts to get smaller after it has reached its peak, this is a sign that the sore will most likely go away on its own. However, sometimes the sores do not go away. They will continue to get bigger and as they grow in size the pain will increase. In this type of case, the sore will need to be treated by a dentist.

When the sore is treated by a dentist, they may prescribe something called an antimicrobial mouthwash. This wash is used to kill the bacteria within the sore. However, this type of treatment isn’t always effective and another type of treatment may be used. A laser innovation by BIOLASE called EPIC may be used not only to treat the sore, but also to get rid of any pain in the area. EPIC soft tissue therapy can be used to remove the canker sore from the mouth.

Overview

Canker sores, also called aphthous ulcers, are small, shallow lesions that develop on the soft tissues in your mouth or at the base of your gums. 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.

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.

Symptoms

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.

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

Minor canker sores

Minor canker sores are the most common and:

Are usually small
Are oval shaped with a red edge
Heal without scarring in one to two weeks

Major canker sores

Major canker sores are less common and:

Are larger 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 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.

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Causes

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
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

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

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.

Prevention

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.

What color are canker sores when they are healing?

Whereas a canker sore is usually painful, oral cancer may or may not cause pain. Canker sores are always flat and usually have a white or yellow center (and turn gray as they're healing). Oral cancer lesions can be flat or raised and are often white or red.

Do canker sores hurt more when healing?

Canker sores can be quite painful within the first few days. Thankfully, the pain lessens during the healing process, which can take about two weeks for the minor or herpiteform types.

Why do canker sores turn white?

Canker sores are small painful lumps that can grow on the lips or inside the mouth. These tiny swellings contain a mixture of WBCs (white blood cells) and bacteria, and some other fluids and look like white-yellowish cysts with a red border.

How do you know when a canker sore is getting worse?

If the sore starts to get smaller after it has reached its peak, this is a sign that the sore will most likely go away on its own. However, sometimes the sores do not go away. They will continue to get bigger and as they grow in size the pain will increase.