Mouth Sores

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What are mouth sores?

Mouth sores also known as mouth ulcers are when the soft tissue of the mouth becomes painful. An ulcer is usually not a cause for concern and will naturally disappear, usually taking no longer than ten days.

If your ulcer has not disappeared after two weeks, contact your dentist so they can assess the area. In some cases, persistent ulcers point towards a more serious underlying condition.

What causes mouth sores?

Mouth sores have no direct link to an ailment, instead usually hormonal or physical factors can cause an ulcer to appear:

  • Biting the soft tissue of the mouth, the inner cheeks.
  • A burn or cut on the soft tissue of the mouth.
  • Stress, tiredness and anxiety.
  • Ill-fitting braces or dentures.
  • A jagged tooth or filling can catch on the soft tissue.
  • Brushing too hard when cleaning the teeth.
  • Genetics can influence ulcers.
  • Medications like beta blockers or NSAIDs (non-steroidal anti-inflammatory drugs).
  • Hormones from pregnancy and menstruation.
  • Quitting smoking.
  • Vitamin deficiencies like vitamin B, D, zinc, folic acid, and iron.

In some cases where there are multiple ulcers, it can be indicative of an underlying issue like hand, foot and mouth disease or Crohn’s disease.

How to prevent mouth sores?

Though mouth ulcers have no one definitive cause, you can implement these preventative measures into your life to reduce the likelihood of having an ulcer.

  • Avoid consuming hot, acidic, spicy, or salty food and drinks.
  • Avoid using toothpaste which contains sodium lauryl sulphate, especially with existing ulcers.
  • Avoiding stressors.
  • Getting between seven and nine hours of sleep a night.
  • Consuming a balanced diet.
  • Avoid smoking and drinking alcohol.
  • Taking vitamins where necessary.
  • Gently brushing the teeth.
  • Staying hydrated.
  • Attending regular dentist appointments.

How to treat mouth sores?

Some recommended over-the-counter treatments include antimicrobial mouthwashes, corticosteroid lozenges, and painkillers in the form of gel, spray, mouthwashes, or tablets.

If you are struggling with persistent or reoccurring ulcers, we recommend attending an appointment with your dentist. In the appointment, your dentist will likely consider the following treatment: Mouthwashes, painkilling gels, sprays, tablets, or creams. Steroids in the form of a spray or tablets may also be offered.

How to spot mouth sores/symptoms?

Mouth ulcers typically look white, yellow, or beige and take a round formation. They are usually surrounded by a red, tender border, in some cases this will not be the case.  The sore may feel painful and sensitive and may tingle or burn when running the tongue along it or when food or drink touches it.

Should you experience any more severe symptoms like consistent and frequent reoccurring ulcers, rashes, fevers, joint pains, or diarrhoea, you should contact your dentist and GP and book an appointment to get to the root cause of the symptoms.


Where are we?

Just a short-walk from the nearest tube and DLR stops, German Dental is conveniently situated in the City of London, opening Monday-Friday from 10am-6pm for appointments.


German Dental Clinic
1-3 College Hill
Lower Ground


Nearby Tube Stations

Cannon Street

Cannon Street

0.2 miles


0.4 miles


0.4 miles

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