Children practicing brushing their teeth to avoid canker sores
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Canker Sores (Aphthous Stomatitis Or Recurrent Mouth Ulcers)

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Medically Reviewed By Colgate Global Scientific Communications

Have you ever been hindered by a stinging pain in the mouth that worsens while eating or drinking? The culprit may be one or more small, white lesions on your cheeks, gums, or the roof of your mouth. They are most likely canker sores, also known as aphthous ulcers. Though harmless and often disappearing on their own, they can cause significant discomfort. Fortunately, there are many ways to manage and prevent them.

Let us explore what is canker sores, their symptoms and causes, and how to find relief. Read on  for home remedies and preventive measures.

What Are Canker Sores?

Canker sores, or aphthous stomatitis, are small, shallow lesions on the mouth's lining.  Affecting one in ten people, they are non-contagious and harmless (non-cancerous) yet painful, making it difficult to eat, drink, and speak. 

These ulcers appear on the cheeks, gums,  tongue, lips, or palate. They can vary in form and severity:

  • Minor: Most common (85%), appearing as tiny, oval-shaped bumps and less than a centimetre wide, causing a burning or tingling sensation. They heal without scarring in a week or two.  

  • Major: Less common type (10%), larger, round bumps that are very painful, inflammation, can last two to six weeks, and often leave scars.

  • Herpetiform: These painful lesions are mostly found in groups or clusters of 10 to 100 tiny, pinhead-sized bumps in an area of the mouth. They are rare, accounting for 5%, and can last for weeks before they heal, with a greater chance of scarring.

What Causes Canker Sores?

Experts have yet to determine what causes canker sores. But here are some of the common causes of canker sores, which include:

  • Trauma or mouth injuries from dental appliances, rough teeth cleaning, or biting cheek or tongue accidentally

  • Emotional stress

  • Hormonal changes or variations in menstrual cycle

  • Food allergies

  • Side effects of some medication

  • Weak immune systems and viral infections

  • Deficiencies of vitamins and minerals, such as iron, vitamin B-12 and folic acid

Sometimes, the occurrence of complex mouth sores can be linked to medical conditions such as:

  • Immunodeficiency diseases such as Behçet's disease, Lupus, HIV and AIDS

  • Gut diseases such as chronic inflammatory bowel disease (Crohn’s disease or Ulcerative colitis) and Celiac disease

Canker Sore Symptoms

The most common canker sore symptom is pain while eating, drinking, or speaking. Other signs include:

  • Small, shallow, or oval lesions that are white, yellow, or grey with a red border.

  • Burning or tingling sensation

  • In severe cases, high fever, fatigue, physical sluggishness, or swollen lymph nodes.

Canker Sore Treatment

Having canker sore inside mouth prevents one from enjoying everyday activities, including eating, drinking, and talking. If you are looking for ways on how to remove canker sores, various canker sore treatments can ease discomfort even while they often heal on their own:

  • Topical medications: Your healthcare provider may prescribe canker sore medicine, including topical medications like creams, ointments, or gels, which can be applied to the affected area using a cotton swab.

  • Mouthwash: Alcohol-free mouthwashes with pain-relieving compounds

  • Oral medication: Anti-inflammatory pills or tablets.

  • Dietary Changes and Supplements: Avoid irritant foods and consider vitamin or mineral supplements if needed.

Canker Sore Home Remedies

It is natural to look for quick home remedies to reduce the pain from the sores, especially if you are having canker sore on tongue. Though not always scientifically backed, some home remedies for canker sores include:

  • Salt Water Rinse: Due to its antibacterial properties, salt has been used in household remedies for various oral problems. Mix a teaspoon of salt in warm water.

  • Applying Ice: Wrap an ice cube in a soft towel and hold it against the sore to reduce the pain of mouth ulcers. 

  • Honey: Known for its healing properties, it can help reduce the lesion size and the pain duration.

How to Prevent Canker Sores?

While there’s no way to prevent canker sores some measures can reduce the risk. They include:

  • Dietary choices: Avoid acidic or spicy foods and beverages and maintain a healthy and balanced diet.

  • Good oral hygiene: Brush with a soft-bristled toothbrush and fluoride toothpaste and floss daily.

  • Addressing the potential cause: Identifying and treating health conditions, such as deficiencies, low immunity, hormonal imbalance, and emotional stress, that trigger sores.

Though painful and irritating, canker sores are common and harmless for many people, unlike cold sores or fever blisters, which are caused by the herpes simplex virus. Understanding the symptoms and causes allows you to manage outbreaks and find relief through treatment options. Preventing them involves avoiding food triggers, including spicy and acidic foods, maintaining  oral hygiene, and leading  a healthy lifestyle. If you are wondering how long do canker sores take to heal or if mouth sores become severe or persistent, consult a healthcare professional for medical advice.

When to See a Dental Professional?

If you are experiencing persistent or severe canker sores, it is vital to consult a dental professional. Seek help if the pain worsens and becomes unmanageable with home remedies and over-the-counter medications, or if the lesions last more than three weeks, as this could indicate an underlying health condition. Additionally, if the canker sores are unusually large or spreading, they require professional advice for a proper diagnosis and effective canker sore treatment. Your dental professional may also recommend a blood test to check for vitamin deficiencies or other conditions that are causing the ulcers.

Frequently Asked Questions

  1. What is the best canker sore treatment?

  2. While they often heal on their own, professional treatment can provide quicker relief. Options include topical or oral medications or alcohol-free mouth rinses.

  3. How long do canker sores last?

  4. Canker sores are harmless and vanish on their own. Minor canker sores last for a week or two. However, major canker sores may take two to six weeks and might leave scars when they heal.

  5. What toothpaste is good for canker sores?

  6. Consult a dental professional for personalised recommendations.

  7. Should I brush my teeth if I have a canker sore?

  8. Yes, even if mouth movement can cause discomfort while having a mouth sore, maintain good dental hygiene, ideally with a soft toothbrush, to avoid aggravating the painful sores.