A mouth ulcer is the loss of part of the delicate tissue lining inside the mouth (mucous membrane)
The most common cause is injury such as biting your cheek
Other causes include certain drugs, chemicals and infectious diseases such as herpes or thrush
In most cases, mouth ulcers are harmless and clear up in a few days
Aphthous ulcers are recurring ulcers with no known cause that affect around 20 per cent of the population
See your doctor if your mouth ulcers don’t clear up within a few days, or if you are troubled by frequent attacks
Mouth ulcer symptoms
The symptoms of a mouth ulcer depend on the cause but may include:
A round sore or sores inside the mouth
Swollen skin around the sores
Tenderness
Problems with chewing or toothbrushing because of the tenderness
Irritation of the sores by salty, spicy or sour foods
Loss of appetite
Mouth ulcers causes
Mouth ulcers can be caused by a wide range of factors including:
Accidental biting of the cheek
Injury from a toothbrush (such as slipping while brushing)
Constant rubbing against misaligned or sharp teeth
Constant rubbing against dentures or braces
Poor oral hygiene
Burns from eating hot food
Irritation from strong antiseptics, such as a mouthwash
Oral thrush infection
Herpes simplex viral infection (cold sore)
Reaction to certain drugs, such as chemotherapeutic agents
Autoimmune diseases (for example, lichen planus)
Syphilis infection
A range of other infections including hand-foot-mouth syndrome
Certain diseases including tuberculosis, AIDS, diabetes mellitus and inflammatory bowel disease
Cancer of the lip
The cause of aphthous ulcers isn’t known
Around one in five adults suffer from recurring bouts of aphthous ulcers, which are mouth ulcers with no known cause
The tongue, gums or mouth lining can be affected
Crops of these tiny off-white ulcers tend to sprout during times of emotional stress or the menstrual period
This has led some researchers to suggest that aphthous ulcers may be caused by an immune system reaction, since the immune system is affected by stress and hormones
The underlying trigger may be a virus or an allergic reaction
Another name for aphthous ulcer is canker sore
Possible complications of mouth ulcers
Untreated, mouth ulcers can occasionally lead to complications including:
Bacterial infection
Inflammation of the mouth (cellulitis)
Tooth abscess
Medical examination for mouth ulcers
It is important to establish the cause of the mouth ulcers
Some of the investigations may include:
Physical examination – mouth ulcers look different depending on their cause
For example, if the ulcer is large and yellow, it was most likely caused by trauma
Cold sores inside the mouth tend to be very numerous and spread around the gums, tongue, throat and inside of the cheeks
A fever also suggests the ulcers may be caused by a herpes simplex infection
Blood tests – to check for signs of infection and iron and folate deficiency
Skin biopsy – a small tag of tissue from the ulcer is taken and examined in a laboratory
Mouth ulcer remedies and treatment options
Most mouth ulcers are harmless and resolve by themselves in a few days
Other types of mouth ulcers, such as the aphthous variety or those caused by herpes simplex infection, need medical treatment
It isn’t possible to speed the recovery of ulcers, but the symptoms can be managed and the risk of complications reduced
The range of treatment options includes:
Avoid spicy and sour foods until the ulcers heal
Drink plenty of fluids
Regularly rinse your mouth out with warm, slightly salted water
Keep the mouth clean
Take pain-killing medication, such as Panadol (paracetamol)
Apply antiseptic gel to the ulcers
Use a medicated mouthwash
Use steroid gels or tablets
Treat aphthous ulcers with anti-inflammatory drugs
Treat ulcers caused by the herpes simplex virus with anti-viral drugs
Treat oral thrush with anti-fungal drugs
Mouth ulcer prevention tips
Suggestions on how to reduce the likelihood of mouth ulcers include:
