Mouth Ulcers: Painful Nuisance Or Something More Sinister?

If you’ve ever had a mouth ulcer, you’ll know they can be a pain. The uncomfortable stinging sensation they create can make eating, drinking and even talking a hassle. So, what actually causes mouth ulcers? How can they be treated and prevented?
To help answer these questions, we’ve enlisted the help of Dr Michelle Groves, a General Practitioner at a family practice with over 20 years’ experience in the medical field.
What are mouth ulcers?
Mouth ulcers, also known as aphthous ulcers, are a common condition that regularly affect significant parts of the population. They consist of one or more shallow, rounded and painful erosions of the delicate mouth tissue. Mouth ulcers are usually a few millimetres across and can last one to two weeks. However, large ulcers can reach up to two centimetres wide and take up to six weeks to heal. They commonly appear inside the cheeks, or on the lips and tongue. For some people, mouth ulcers can recur for days or every few months.
What causes mouth ulcers?
There are a wide range of conditions and factors that can cause mouth ulcers to appear. Here are some of the more common causes:
- Poor dental hygiene
- Stress
- Menstruation
- Vitamin B12, iron or folate deficiency
- Physical trauma – sharp teeth, poorly fitted dentures, hot foods
- Chemical trauma – acidic foods, medications
- Viral infections – herpes simplex virus, Coxsackie (commonly known as hand, foot and mouth disease)

In very rare circumstances ulcers can become a recurring problem due to systemic and more serious medical conditions, such as:
- Inflammatory bowel disease
- Coeliac disease
- Behcet’s disease – a rare disease causing swelling of blood vessels
- Immune deficiency
- Malignancy – for example leukaemia, Lupus, HIV
- Some skin disorders
- Bacterial infections – like syphilis and TB
- Oral cancer
Treatment options
Most simple ulcers tend to resolve themselves within two weeks. However, symptoms can be managed by topical treatments applied to the problem part of the mouth such as mouthwashes, ointments and gels. These treatments can include:
- Warm saline mouthwash – dissolve half a teaspoon of salt in a glass of warm water and rinse mouth frequently
- Antiseptic mouthwash or spray – topical chlorhexidine, for example
- Anti-inflammatory mouthwash/spray – such as benzydamine sprays
- Steroid spray or tablets

How to help prevent mouth ulcers
It may not be possible to prevent all mouth ulcers as in some cases they can be due to underlying medical conditions or a family genetic trait. There are also many potential causes of mouth ulcers ranging from deficiencies and hypersensitivities to emotional stress.
One way of helping to prevent mouth ulcers is by having good oral health. It’s important to brush your teeth gently with a soft bristled brush and to consider steering clear of foaming agents in pastes (such as sodium lauryl sulphate). Regular check-ups with your dentist can also help you to avoid mouth ulcers.
Additionally, diet and nutrition can play a very important role in prevention. Iron deficiency can be a common cause of mouth ulcers. Vegetarians and vegans can be particularly vulnerable to developing an iron deficiency, whilst women can also become deficient in iron due to their periods. Several food preservatives (E210-E219), chocolate, tomatoes, nuts, cheese, wheat and berries have also been shown to cause recurrent mouth ulcers. Therefore, a diet rich in Vitamin C and B which is found in fruit, vegetables and whole grains, as well as iron in leafy greens, is recommended.
If you are experiencing recurrent mouth ulcers or if they are causing severe symptoms, then you should consult your family doctor or dentist. A careful examination and blood tests may be required if an underlying chronic condition is suspected. A biopsy may also be needed if the cause cannot be determined.
About Dr Michelle Groves
Dr Groves holds a Bachelor of Medicine from Southampton University in the UK, is a Fellow of the Royal Australian College of General Practitioners, a Diplomate of the Royal College of Obstetricians and Gynaecologists in the UK as well as being extensively experienced through her previous role as a family planning and sexual health doctor. She emigrated to Australia in 2011 with her husband and twin boys and currently practises as a GP at Paradise Point Surgery.
Image source: whitecoat.com.au. Cover Image Source: Olga Aniven (Shutterstock)
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