A guide to aphthous stomatitis (canker sores): why they happen and how long they take to heal
Aphthous stomatitis is a condition in which a round, whitish hollowed-out ulcer forms inside the cheek or lip and stings, and is commonly called a mouth sore or a tongue bump. In Korea, the National Health Information Portal explains that aphthous stomatitis is the most common form, making up about 20% of oral mucosal diseases, and heals within 10 to 14 days without scarring. The cause has not yet been clearly identified, and it is distinguished from infectious stomatitis that spreads to other people.
Key facts
| How common | About 20% of oral mucosal diseases, with higher frequency in East Asians (source: KDCA National Health Information Portal) |
|---|---|
| Size and shape | 2 to 10 mm, clear border, red edge and yellow center (source: KDCA National Health Information Portal) |
| Most common type | Minor aphthous stomatitis, known as tongue bumps, at about 80% (source: KDCA National Health Information Portal) |
| Healing time | Within 10 to 14 days, leaving no scar (source: KDCA National Health Information Portal) |
| Family history | Found in about one third of patients (source: KDCA National Health Information Portal) |
| First symptom | A tingling, burning feeling 2 to 48 hours before the ulcer appears (source: Seoul National University Hospital) |
What does aphthous stomatitis look like?
The National Health Information Portal explains that the ulcers of aphthous stomatitis usually number one or more, are about 2 to 10 mm in size, and have a clear border, a red edge and a yellow center. They mainly form on soft lining such as the inside of the cheek, the inside of the lip and the side of the tongue, and are rare on the gums or the hard palate.
According to Seoul National University Hospital's medical information, a tingling or burning feeling comes first 2 to 48 hours before the ulcer appears, and within a few hours of a red spot forming it turns into a white ulcer. The ulcer can grow slightly over 48 to 72 hours, so there is no need to worry much just because it gets bigger in the first few days.
Aphthous ulcers often form several at a time, and Seoul National University Hospital's medical information explains that an episode usually produces 2 to 6 ulcers. Conversely, if only one ulcer stays in the same place for a long time, causes other than aphthous ulcers should be considered.
What types of aphthous stomatitis are there?
The National Health Information Portal explains that minor aphthous stomatitis, well known as tongue bumps, is the most common type and makes up about 80% of aphthous stomatitis. Seoul National University Hospital's medical information describes the types by size and depth as below. The healing time and treatment differ by type, so pay attention to the size of the ulcer.
- Minor aphthae: about 0.3 to 1 cm across, heal in 10 to 14 days without scarring
- Major aphthae: 1 cm or more across and deeply hollowed, lasting from a few weeks to several months
- Severe form: a wide area of lining is covered with deep ulcers that merge, making talking and chewing hard
Why does aphthous stomatitis happen?
The exact cause has not yet been identified. By the National Health Information Portal, about one third of aphthous patients have a family member with the same mouth sores, and Seoul National University Hospital's medical information names heredity as the best-known factor and advises that if even one parent has this condition, the child's risk is higher.
Other related factors named are a shortage of serum iron, folate and vitamin B12, local immune abnormalities, injuries to the lining from brushing or eating, anxiety and mental stress, menstruation, and food allergy. Seoul National University Hospital's medical information explains that hot food, injuries to the cheek and tongue, fatigue and stress can make aphthous symptoms worse. Smoking is also one of the local causes named in the same material.
How is aphthous stomatitis treated?
Minor aphthae often heal on their own, and the aim of treatment is to reduce pain and shorten the healing time. The drugs introduced by the National Health Information Portal are topical anesthetic mouthwash such as lidocaine, antibacterial mouthwash such as tetracycline or chlorhexidine, steroid ointment and mucosal protectants, and in severe cases oral steroids can also be used.
Seoul National University Hospital's medical information explains that starting to apply medicine at the stage of a small lesion helps shorten the time of illness. For large lesions, a steroid drug may be held against the ulcer on gauze so it stays in contact for a long time, or injected into the lesion, and if secondary infection is suspected, an antibacterial mouthwash or antibiotic is used.
When it hurts too much to eat, a method of briefly reducing pain with an anesthetic drug applied just before a meal is also introduced in Seoul National University Hospital's medical information. Even while using medicine, avoid foods that irritate the ulcer and keep brushing gently so as not to touch the ulcer.
When is aphthous stomatitis related to another disease?
If an aphthous ulcer is unusually large and deep, gets worse over several months, or comes with other symptoms, tests are needed. Seoul National University Hospital's medical information explains that in such cases blood tests check iron, folate, vitamin B12 and ferritin levels, and if there is an abnormality, internal medicine must check for malabsorption.
The National Health Information Portal explains that Behcet's disease, which rarely causes large aphthous ulcers, can leave permanent mucosal damage. If you have eye symptoms, skin lesions or genital ulcers along with mouth ulcers, be sure to mention them at the visit.
Common myths and facts
Myth: Aphthous stomatitis spreads to other people.
The National Health Information Portal classifies aphthous stomatitis as non-infectious stomatitis. Mouth sores that spread are infectious stomatitis such as herpetic stomatitis and hand-foot-and-mouth disease.
Myth: Frequent mouth sores mean you have a serious disease.
Aphthous stomatitis is the most common oral mucosal disease and usually heals within 10 to 14 days without scarring. However, if the ulcer is large, lasts long or comes with other symptoms, tests are needed.
Frequently asked questions
Are tongue bumps and aphthous stomatitis the same thing?
The National Health Information Portal explains that what is well known as tongue bumps is minor aphthous stomatitis, the most common type. If a small, stinging ulcer has formed at the tip or side of the tongue, it is mostly this type, but if it lasts long or keeps getting bigger, check whether there is another cause.
Are there foods to avoid when I have aphthous stomatitis?
Seoul National University Hospital's medical information advises avoiding foods that can irritate the ulcer and names hot food as an aggravating factor. Try cutting back until it heals on foods that scratch or sting the ulcer, such as spicy seasoning, sour fruit and crunchy snacks. Quitting alcohol and smoking is also recommended, so it is good to avoid them during this time.
When is the best time to start applying aphthous stomatitis ointment?
There is an explanation that starting medicine while the lesion is small helps shorten the duration, so it is good to get an exam and a suitable prescription just when the tingling and ulcer start. Follow the instructions given when prescribed for how often and how to apply.
How often does aphthous stomatitis recur?
The National Health Information Portal explains that aphthous stomatitis tends to recur, and Seoul National University Hospital's medical information advises that many patients have a recurrence 3 to 4 times a year. If it is more frequent than this or several keep forming at a time, get tested for the cause. According to Seoul National University Hospital's medical information, the first symptoms mainly appear at ages 10 to 20, so if mouth sores have continued since childhood, mention that history as well.
How is a large aphthous ulcer over 1 cm different?
Minor aphthae heal without scarring, but Seoul National University Hospital's medical information explains that major aphthae over 1 cm are deeply hollowed and can last from a few weeks to several months. A large ulcer may not be enough to treat with topical treatment alone and the treatment method changes, so it is good to get an exam early when one forms.
Related topics
- Mouth sores and oral pain
- Mouth sores and oral pain
- Recurring mouth sores
- Mouth sore care
- Ulcer that won't heal