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Mouth ulcers are painful areas in the mouth and gums. They are also known as canker sores.
While mostly harmless, mouth ulcers can be extremely uncomfortable and make it difficult for some people to eat, drink, and brush their teeth.
Mouth ulcers range in size, and the exact symptoms of the mouth ulcer will depend on what type of ulcer a person has.
Fast facts on mouth ulcers:
- Most mouth ulcers are recurring nuisances that are benign.
- Quitting smoking and acidic foods can aggravate mouth ulcers.
- It is important to note that a doctor or dentist should examine any new ulcer and any ulcer lasting longer than 3 weeks.
- For most people, mouth ulcers will clear up within 2 weeks.
The exact cause of mouth ulcers is still not known and varies from person-to-person. Still, there are some common causes and several factors that may aggravate mouth ulcers, including the following:
- citrus fruits and other foods high in acidity or spice
- biting the tongue or inside of the cheek
- braces, poor-fitting dentures, and other apparatus that may rub against the mouth and gums
- a deficient filling
- stress or anxiety
- hormonal changes during pregnancy, puberty, and menopause
- medications including beta-blockers and pain killers
- genetic factors
Some people may develop ulcers as a result of a different medical condition or a nutritional deficiency.
Conditions such as celiac or Crohn’s disease, vitamin B12 or iron deficiency, or a weakened immune system may all trigger ulcers to form.
Are mouth ulcers cancerous?
Mouth cancer and mouth ulcers are distinctive in their symptoms. However, as mentioned earlier, new or persistent ulcers require checking.
There are some fundamental differences between mouth ulcers and what might be cancer:
- Mouth ulcers are often painful whereas mouth cancer is not.
- Mouth ulcers will clear up in about 2 weeks, whereas mouth cancer will not go away and will often spread.
- Mouth cancer patches may be rough, hard, and not easy to scrape off.
- Mouth cancer is often a mix of red and white areas or large white areas that appear on the tongue, the back of the mouth, the gums, or on the cheeks.
- Mouth cancer is often linked to heavy drinking or tobacco use.
In many cases, the pain and discomfort from mouth ulcers will lessen in a few days and then disappear in about 2 weeks with no need for treatment.
For people with much more painful or frequent recurrence of mouth ulcers, a dentist may prescribe a solution to reduce swelling and lessen pain.
Also, a dentist may prescribe an antimicrobial mouthwash or an ointment to be applied directly to the infected patch. This can help to ease discomfort. Various mouth ulcer treatments are also available to purchase online.
Standard ulcers appear on the inner cheeks and last for about 1 week. Most are harmless and clear up with no medical intervention.
There are three main types of mouth ulcers. These include:
Herpetiform ulceration (HU)
Herpetiform ulcers are a subtype of aphthous ulcers and get their name because they resemble the sores associated with herpes. Unlike herpes, HU is not contagious. HU ulcers recur very quickly, and it may appear that the condition never gets better.
This type can range in size from about 2 millimeters (mm) up to 8 mm across. These ulcers typically take up to 2 weeks to get better and will cause minor pain.
Bigger than minor ulcers, major ulcers are often irregular in shape, may be raised, and penetrate deeper into the tissue than minor ulcers. They can take several weeks to go away and are likely to leave scar tissue when they clear.
Ulcers can be painful, and the pain can be made worse by food, drink, and poor oral hygiene.
HU lesions may:
- appear as extremely painful ulcers in the mouth
- recur very quickly, so infections seem continuous
- increase in size, eventually coming together to form a large, ragged ulcer
- take 10 or more days to heal
- appear anywhere in the mouth
They tend to be found in more females than males and are more common in older adults.
Symptoms of minor and major ulcers include:
- one or more painful sores that may appear on the cheeks, the roof of the mouth, or the tongue
- the appearance of round lesions that have red edges and are yellow, white, or gray in the middle
During more extreme outbreaks of mouth ulcers, some people may experience fever, sluggishness, and swollen glands.
People who frequently get mouth ulcers may find it difficult to know when to see a doctor.
There are some situations, however, where a person should see a doctor as soon as possible. Some of these circumstances include:
- the appearance of a non-painful ulcer in one or more areas of the mouth
- unusual ulcers that appear in a new spot in the mouth
- ulcers that are spreading
- ulcers lasting longer than 3 weeks.
Others may want to seek medical attention or treatment for their ulcers if:
- they are particularly painful or big
- a fever appears
- they develop after starting a new medication
- secondary bacterial infections
Mouth ulcers have no known cure and typically recur in the mouth throughout a person’s life.
Though the appearance of an ulcer may be inevitable, there are some things people can do to lessen the severity of or reduce the number of times they suffer from an outbreak.
Some prevention methods include:
- talking to a doctor about changing medications that are known to cause ulcers
- avoiding foods that can either trigger or worsen symptoms
- keeping the mouth clean with daily brushing and flossing
- avoiding triggers known to cause outbreaks in the past
Thankfully, mouth ulcers tend to clear up on their own, and the pain associated with an ulcer typically disappears within a couple of days.
There are some medications in the form of ointments and solutions that may help with pain and swelling, but these are often not necessary for a person to make a full recovery.
To prevent future outbreaks, people should try to reduce stress and anxiety as much as possible.