Mouth sores are lesions that develop on the soft tissues in the mouth and on the lips and gums. They are a common condition and can be painful. Most mouth sores are harmless and disappear within two weeks.

However, there are different types of sores and some can be a pointer to a more serious health issue. Your dentist can determine the type of sore and recommend a suitable treatment course. If the sore lingers, is larger than half an inch in diameter - or has white patches - you would be advised to consult with a healthcare provider.

What Causes Mouth Sores?

The lesions resulting from a mouth sore will differ in color from the surrounding soft tissue. They could be red, purple, yellow, or white depending on the type of sore. Inflammation and some degree of discomfort are also likely.

Mouth sores can be caused by everyday bad habits, injury, or an underlying health condition. These include:

  • Tobacco use
  • Medications
  • Stress
  • Irritation from orthodontics such as braces
  • Biting your lip or the inside of the cheek
  • Aggressive brushing of the teeth
  • Burning the inside of your mouth
  • Celiac disease
  • Crohn’s disease
  • Bacterial, viral, or fungal infection
  • Autoimmune disorders
  • Anemia

The symptoms and causes of sores depend on the type of sore. The following are examples of different mouth sores.

1. Canker Sores

This is one of the most common mouth sores, affecting around 20% of people during their lives. An area of redness with small white or yellow ulcers indicates a canker sore. They tend to be harmless, are not contagious, and usually clear up within one or two weeks.

2. Cold Sores

Another common sore, with blisters forming on the lips or close to the mouth. They are caused by the herpes simplex virus and are contagious for up to 15 days, the virus being passed on through kissing or sharing food, utensils and cosmetics. They may be preceded by a tingling sensation and can last between two to six weeks.

3. Oral Thrush

The signs of oral thrush are white lesions on the tongue and on the inside of the mouth. It is caused by a yeast infection resulting from Candida overgrowth, a yeast that occurs naturally in the body. Normally harmless and unlikely to be passed on to others, oral thrush can be treated and cleared within 14 days with the correct anti-fungal medication.

4. Leukoplakia

This condition is denoted by thick white patches in the mouth. It is a common mouth sore for people who use tobacco. While the sores tend to clear up of their own accord and prove harmless, the condition could increase the risk of oral cancer. Regular dental appointments help spot this condition earlier.

5. Gingivostomatitis

These sores appear most often in the mouth and on the gums of children. They are similar to canker sores and can be the result of either a bacterial or a viral infection. Gingivostomatitis can also be caused by poor oral hygiene. The sores may be painful and a reason why your child does not want to eat.

6. Pemphigus Vulgaris

The mouth blisters arising from this condition can be sore and may bleed. Pemphigus Vulgaris is an auto-immune disease that sees healthy tissues targeted by your misfiring immune system. Fortunately, the condition is rare and can generally be treated with systemic corticosteroids, although it may take up to three months for the treatment to kick in.

7. Oral Cancer

Oral cancer can be signified by ulcers and red and white patches. Unlike canker and cold sores, these lesions do not heal. You may also experience bleeding, swollen lymph nodes in the neck, ear pain and loss of weight. A healthcare provider can carry out a biopsy to assess for cancer. An early diagnosis of oral cancer could improve a patient’s outcome.

When Should I See My Dentist?

Regular dental appointments are a key part of maintaining good oral health care. Your dentist can spot oral health problems early when they can be easier to treat. This includes mouth sores and mouth blisters.

However, if you have ulcers or lesions develop between dental appointments you can consult with your dentist for peace of mind. Sores are usually harmless and will clear within a week or two, depending on the type of sore.

In most instances, your dentist can assess and treat sores and mouth blisters. However, if you experience the following conditions you should consult with a healthcare provider:

  • persistent sores that won’t heal
  • recurring sores
  • lesions larger than half an inch in diameter
  • fever
  • severe pain
  • white patches on sores
  • sores after taking a new medication
  • sores having started cancer treatment

Treatments and Prevention

If your sores are caused by a bacterial or viral infection, you could be prescribed medication to treat the condition. You may also be given pain relief, a steroid gel, or anti-inflammatories depending on the type of sore and the severity of the condition.
However, as most sores will gradually heal, your dentist may recommend ways to ease any discomfort and hasten the healing process from the comfort of your home. These include:

  • rinsing your mouth with warm salt water
  • eating cold foods like sherbet
  • taking over-the-counter pain relief
  • avoiding tobacco
  • avoiding the temptation to squeeze or pick the sores

As always, prevention is preferable. Ways to help prevent sores include:

  • good oral care practice
  • a balanced diet
  • stay hydrated
  • minimize alcohol intake
  • avoid tobacco
  • develop ways to reduce stress
  • use lip balm of at least SPF 15 when outdoors
  • avoid hot foods and drinks

Mouth sores often clear within a week or two. However, some types of sores can indicate a more chronic health issue. Your dentist can diagnose the type of sore and recommend the appropriate treatment. They will also recognize any sores that could be more problematic and refer you to the appropriate healthcare provider.