Thrush: Definition, Causes, Symptoms, Diagnosis, Treatment and Prevention

They are superficial ulcers of the oral mucosa, not contagious or infectious.

The mouth ulcer forms mainly on the inside of the lips and cheeks, the tongue, the roof of the mouth, the gums or the throat.

Mouth ulcers are always painful, can cause discomfort to speak, eat or swallow, and can negatively affect a patient’s quality of life.

Some people feel itching or a local growth as a precursor ( prodrome ) sign 24 to 48 hours before the onset of the canker sore.

There are many treatments for canker sores, but the cause of canker sores is still unknown.

There is talk of repeated canker sores or recurrent canker sores when mouth ulcers appear periodically.

Mucositis are canker sores, or multiple sores, that occur after chemotherapy or radiation therapy in certain types of cancer .

When mouth ulcers occur repeatedly, it is called aphthosis . Often the first outbreak of thrush occurs during childhood.

Mouth sores are common, around 17% of the population is affected at some point in their life.

Causes of mouth ulcers

Mouth ulcers are not infectious, so they are not contagious. There is no definite cause behind mouth ulcers.

Several factors, including heredity, could contribute to this.

However, scientists have observed factors that tend to trigger symptoms in patients such as:

  • A small wound inside the mouth. Which can be caused by improper denture fit, oral surgery, too vigorous use of the toothbrush, a dent in the cheek, etc.
  • Physical tiredness and stress . These often precede the appearance of canker sores.
  • Allergies or sensitivities. The literature relates the recurrence of mouth ulcers to allergies or sensitivities to foods such as coffee, chocolate, eggs, nuts, cheese, sensitivities to acidic foods such as strawberries, citrus fruits and pineapples, and preservatives such as benzoic acid and cinnamaldehyde 1-4.
  • Dietary deficiency of vitamin B12, zinc, folic acid, or iron.
  • Quit the habit of smoking. Mouth ulcers can occur during smoking cessation.
  • An infection with the bacteria Helicobacter pylori, the same bacteria that can cause an ulcer in the stomach or small intestine.
  • Some drugs. Anti-inflammatory drugs (ibuprofen and others), beta blockers (propanolol and others), and alendronate (against osteoporosis) can cause ulcers.
  • Hormonal changes related to the menstrual cycle, possibly. Mouth ulcers tend to appear during menstruation, but this link is uncertain.
  • Toothpastes and mouthwashes that contain sodium lauryl sulfate.
  • Bacterial, viral, or fungal infections.

Mouth ulcers can also be a sign of conditions that are more serious and require medical treatment, such as:

  • Celiac disease (a condition in which the body cannot tolerate gluten).
  • Inflammatory bowel disease
  • Mellitus diabetes.
  • Behcet’s disease (a condition that causes inflammation throughout the body).
  • When the immune system malfunctions causing the body to attack healthy cells in the mouth instead of viruses and bacteria.
  • VIH / PAGE.

Symptoms of canker sores

There are three types of canker sores: minor, major, and herpetiform.

Minor: Small mouth ulcers are small round or oval ulcers that heal in one to two weeks without scarring.

Major: the main canker sores are larger and deeper than the minor ones. They have ragged edges and can take up to six weeks to heal. Major mouth ulcers can lead to long-term scarring.

Herpetiform: Herpetiform canker sores are exactly sized, occur in groups of 10 to 100, and often affect adults.

This type of mouth ulcer has ragged edges and often heals without scarring in one to two weeks. A doctor should be consulted if you develop any of the following symptoms:

  • Unusually large mouth ulcers.
  • New mouth ulcers before old ones heal.
  • Sores that persist for more than three weeks.
  • Sores that are painless.
  • Mouth ulcers that spread to the lips.
  • Pain that cannot be controlled with over-the-counter or natural medicines.
  • Serious eating and drinking problems.
  • High fever or diarrhea every time canker sores appear.

In those situations such as in cases where the mouth ulcers do not disappear after 3 weeks, if the mouth ulcers return frequently or if new symptoms appear, a doctor should be seen urgently.

Diagnosis of thrush

Your doctor will be able to diagnose mouth ulcers through a visual exam.

If you have frequent and severe mouth ulcers, your doctor may order tests to look for other medical conditions.

The pain usually lasts 2 to 5 days. However, ulcers may take 1 to 3 weeks to heal.

Canker sores are painful, round or oval wounds that occur from outbreaks.

To make the diagnosis of a mouth ulcer, the doctor relies on several characteristics:

  • The yellowish or grayish background.
  • The infiltrated base (if the canker sore is taken between the fingers, the entire area can be felt to be discreetly indurated).
  • The edges are clear and surrounded by a bright red halo.

If in addition to the canker sores, red eyes, joint pain, persistent diarrhea or abdominal pain are present, it is important to consult without delay.

Similar ulcers can be caused by a chronic disease, such as inflammatory bowel disease (called Crohn’s disease or ulcerative colitis), celiac disease, or Behçet’s disease.

Also, canker sores can resemble mucositis, which is an inflammation of the lining of the mouth sometimes creating small lesions.

People whose immune systems are weakened (due to HIV infection or cancer treatment, for example) are more likely to get ulcers that can be mistaken for canker sores.

Treatment of mouth ulcers

Most canker sores don’t need treatment. However, there are a number of treatments that can decrease pain and healing time. These include:

  • Use a salt water rinse and baking soda.
  • Put milk of magnesia, corticosteroids, or antacids on the mouth ulcer.
  • Cover mouth ulcers with baking soda paste.
  • Use benzocaine products (topical anesthesia) such as Orajel or Anbesol.
  • Apply ice to the canker sores.
  • Using a mouthwash that contains a steroid to reduce pain and swelling.
  • Using topical antihistamines .
  • Placing wet tea bags on canker sores.
  • Take nutritional supplements such as folic acid, vitamin B-6, vitamin B-12, and zinc.
  • Try natural remedies like chamomile tea, echinacea, myrrh, and licorice root.

The purpose of treatment is to relieve symptoms.

The cause, if known, must be treated, gentle and thorough oral hygiene can alleviate some of the symptoms.

You should avoid consuming hot or spicy foods that often increase the pain of mouth ulcers.

The result varies depending on the cause of the ulcer. Many mouth ulcers are harmless and heal without treatment.

However, there are several types of cancer that can appear first as a mouth ulcer that does not heal.

Possible complications arise from squamous cell carcinoma, cellulitis of the mouth, secondary bacterial infection, dental infections (dental abscesses), oral cancer.


Good oral hygiene can help prevent some types of mouth ulcers, as well as some complications from mouth ulcers.

Good oral hygiene includes brushing your teeth at least twice a day, flossing at least daily, and getting regular professional dental exams and cleanings.

You can take steps to reduce the appearance of mouth ulcers.

Avoiding foods that irritate the mouth can help.

That includes sour fruits like pineapple, grapefruit, oranges, or lemon, as well as nuts, potato chips, or anything else spicy.

Instead, choose whole grains and alkaline (non-acidic) fruits and vegetables.

Eat a healthy, well-balanced diet and take a daily multivitamin.

Try to avoid talking while chewing your food to reduce accidental bites.

Reducing stress and maintaining good oral hygiene by flossing every day and brushing after meals can also help.

Finally, get enough sleep and rest. This will not only prevent mouth ulcers, but a host of other illnesses as well.

Some people find that avoiding stiff-bristle toothbrushes and mouthwashes that contain sodium lauryl sulfate also help.

Your dentist can give you wax to cover dental or orthodontic devices that have sharp edges.