Mouth ulcer vs. canker sore: What’s the difference?
“Mouth ulcer” is a broad term that describes any sore or ulceration inside your mouth. As we mentioned earlier, canker sores are the most common type of mouth ulcer. They affect about 20% of the general population. Many people use the terms “mouth ulcer” and “canker sore” interchangeably.
You might get a canker sore if you have a folate, vitamin B or iron deficiency. But in most cases, canker sores appear without a known cause and for no apparent reason. They can also recur (return), meaning they come and go over the course of your lifetime.
Some people confuse canker sores with cold sores (fever blisters), but they’re very different. A canker sore appears inside your mouth. A cold sore forms outside your mouth, usually on your lips. Canker sores aren’t contagious, but cold sores are.
How do you know if your mouth ulcer is bad?
Anytime you have a mouth sore that lasts longer than three weeks, schedule a visit with your provider. Mouth ulcers that don’t go away could point to other underlying health conditions.
Are mouth ulcers a sign of cancer?
Usually not, but it’s possible. A mouth ulcer that doesn’t go away could be a sign of oral cancer. In most cases of mouth cancer, mouth ulcers appear on or under the tongue.
Most mouth ulcers are harmless. But if you have a mouth sore that won’t heal, you should talk to a healthcare provider.
A note from Cleveland Clinic
Most mouth ulcers aren’t dangerous. But they can be a huge inconvenience. Mouth sores cause pain that can keep you from enjoying the things you love, like eating certain foods, drinking comfortably, playing an instrument or kissing your partner. Your mouth ulcer will probably go away within two weeks. In the meantime, you can try over-the-counter medications and home remedies to reduce pain until the sore heals. If you have a mouth ulcer that doesn’t heal after three weeks, schedule a visit with a healthcare provider. You might have an underlying condition that needs treatment.
FAQs
Anyone can get them, and while they can sometimes be a sign of an underlying medical condition, they're usually nothing to worry about. They resolve on their own and you move on with your life. But not all mouth ulcers are canker sores. Sometimes, these conditions require medical intervention.
Can mouth ulcers be harmful? ›
Mouth ulcers are painful sores that appear in the mouth. They're uncomfortable but they're usually harmless. Most clear up by themselves within 1 to 2 weeks. Mouth ulcers are common and can usually be managed at home, without seeing your dentist or GP.
How do I know if my mouth ulcer is serious? ›
See a dentist or GP if your mouth ulcer:
lasts longer than 3 weeks. is different to other mouth ulcers you've had before, for example if it's bigger than usual or near the back of your throat.
Why are mouth ulcers so annoying? ›
Regular mouth ulcers are likely due to an underlying condition called Aphtous Stomatitis. The ulcer itself can be very painful on contact and can cause constant irritation. If it is swollen it can interfere with one's bite and be bitten on accidentally.
Should you leave mouth ulcers alone? ›
They can certainly be a pain, but in most cases canker sores aren't serious and should go away on their own.
Are mouth ulcers caused by bad hygiene? ›
Poor oral hygiene can increase the risk as ulcers can come about due to plaque/bacteria on teeth. An unbalanced diet, especially if you are lacking in Iron, Vitamin B12 or C. Excessive smoking – as this smoke can damage tissue in the mouth.
Why am I getting so many ulcers in my mouth? ›
The most common cause is injury (such as accidentally biting the inside of your cheek). Other causes include aphthous ulceration, certain medications, skin rashes in the mouth, viral, bacterial and fungal infections, chemicals and some medical conditions. An ulcer that won't heal may be a sign of mouth cancer.
Do mouth ulcers mean you are run down? ›
You can get mouth ulcers that keep coming back, mainly at times when you're particularly stressed, anxious or 'run down'. Some women can also develop them during hormonal changes such as pregnancy or their monthly period.
What can be mistaken for mouth ulcers? ›
While folate deficiency can cause anemia, other types of anemia, like iron deficiency anemia, can cause mouth sores as well. These sores may look like small mouth ulcers or canker sores and be white, gray, yellow, or red in color. Folate deficiency may also cause additional symptoms, including: fatigue.
What is the fastest way to cure a mouth ulcer? ›
How to cure mouth ulcers fast naturally
- Drink plenty of water.
- Practice good oral hygiene to keep your mouth as clean as possible.
- Rinse your mouth with warm saltwater a few times each day.
- Make a mixture of equal parts hydrogen peroxide and water and rinse your mouth twice a day.
Nutritional deficiency
It has been noted in several studies that canker sores are either caused or triggered further when there is a deficiency of folic acid, zinc, or iron in the human body. Deficiencies of calcium can also cause canker sores, but more than causing them, calcium deficiency can worsen the situation.
When should you worry about mouth sores? ›
Contact your health care provider if: The sore begins soon after you start a new medicine. You have large white patches on the roof of your mouth or your tongue (this may be thrush or another type of infection). Your mouth sore lasts longer than 2 weeks.
Can you put salt directly on a mouth ulcer? ›
You would never pour salt directly on a wound, but salt water rinses are painless and have been used medicinally for centuries with great success. Milk of Magnesia placed directly on the sore with a cotton swab several times a day is especially beneficial if done following the salt water rinse.
Should I brush my teeth if I have mouth ulcers? ›
Even though moving your mouth can make the pain worse, you should brush your teeth just as well as you usually do when you don't have a canker sore. A soft brush can help to prevent injuries to your gums that could increase the risk of new canker sores developing.
Is it safe to kiss with mouth ulcers? ›
No. Canker sores aren't herpes or any other type of sexually transmitted infection (STI). In fact, they're not contagious at all. So, you can't spread them through kissing or sexual contact.
Can mouth ulcers be harmless? ›
A mouth ulcer is the loss or erosion of the delicate lining tissue of the mouth (mucous membrane). The most common cause is injury, such as accidentally biting the inside of your cheek. In most cases, mouth ulcers are harmless and resolve by themselves in 10 to 14 days without the need for treatment.
What happens if mouth ulcer is not treated? ›
Mouth ulcers are rarely contagious and usually go away after 1 to 2 weeks, even without treatment. If you get a mouth ulcer that is large, is extremely painful, or lasts for a long time without healing, seek the advice of a doctor or dentist.
Can a mouth ulcer be cancerous? ›
Ulcers that do not heal
A broken area in the lining of the mouth (ulcer) that will not heal is a common symptom of mouth cancer.
What diseases are mouth ulcers a symptom of? ›
Mouth ulcers are caused by many disorders. These include canker sores, leukoplakia, gingivostomatitis, oral cancer, oral lichen planus, oral thrush, and similar disorders.
Can mouth sores be serious? ›
Frequent or lasting mouth sores, which may be a sign of problems such as a serious skin disorder called pemphigus, celiac disease, inflammatory bowel disease, Behcet's disease, an autoimmune disease, anemia, or HIV. In rare cases, they may be a sign of oral cancer or leukemia.
