Mouth Ulcers: Causes, Treatment, and When to See a Dentist
Almost everyone has experienced the sharp, stinging pain of a mouth ulcer at some point in their lives. These small, painful lesions can make eating, drinking, and even speaking incredibly uncomfortable. While most mouth ulcers are harmless and resolve on their own within a week or two, recurring or persistent ulcers can be a sign of an underlying health issue or require professional dental intervention.
In this comprehensive guide, the team at Your Family Dentist explores the common causes of mouth ulcers, effective home treatments, and the critical warning signs that indicate you need to schedule an appointment with your dentist.
What Are Mouth Ulcers?
Mouth ulcers, also known as canker sores or aphthous ulcers, are small, shallow lesions that develop on the soft tissues inside your mouth—such as the inside of your cheeks, lips, underneath your tongue, or at the base of your gums. They are typically round or oval with a white or yellowish centre and a red, inflamed border.
It is important to note that mouth ulcers are not the same as cold sores (fever blisters). Cold sores are caused by the herpes simplex virus, are highly contagious, and typically appear on the outside of the lips. Mouth ulcers occur strictly inside the mouth and are not contagious.
Common Causes of Mouth Ulcers
The exact cause of mouth ulcers is often unclear, but they are generally triggered by a combination of factors. The most common culprits include:
1. Minor Tissue Trauma
Physical injury to the delicate lining of the mouth is the most frequent cause of isolated ulcers. This can happen due to:
- Accidentally biting the inside of your cheek or lip.
- Vigorous or aggressive tooth brushing.
- Eating hard, sharp, or abrasive foods (like potato chips or crusty bread).
- Irritation from poorly fitting dentures, broken teeth, or sharp orthodontic wires and braces.
2. Stress and Anxiety
Emotional stress and anxiety are known to compromise the immune system, making you more susceptible to developing aphthous ulcers. Many people notice that they tend to get mouth ulcers during particularly stressful periods at work or school.
3. Dietary Triggers and Deficiencies
Certain foods can irritate the mouth or trigger an allergic response that leads to ulcers. Common dietary triggers include highly acidic foods (citrus fruits, tomatoes, pineapples), spicy foods, and chocolate. Furthermore, nutritional deficiencies—particularly a lack of Vitamin B12, zinc, folic acid, or iron—are strongly linked to recurrent mouth ulcers.
4. Hormonal Changes
Many women experience mouth ulcers that coincide with hormonal fluctuations, such as during their menstrual cycle or pregnancy.
5. Underlying Medical Conditions
In some cases, frequent or severe mouth ulcers can be a symptom of an underlying systemic condition, such as:
- Coeliac disease or inflammatory bowel diseases (like Crohn’s disease).
- A weakened immune system.
- Reactive arthritis.
How to Treat Mouth Ulcers at Home
Most minor mouth ulcers will heal on their own within 7 to 14 days without leaving a scar. However, you can manage the pain and speed up the healing process with these home remedies and over-the-counter treatments:
- Saltwater Rinses: Dissolve half a teaspoon of salt in a glass of warm water and swish it around your mouth for 30 seconds before spitting it out. This helps reduce inflammation and keeps the area clean.
- Avoid Irritants: Steer clear of spicy, salty, or acidic foods and beverages until the ulcer has healed. Stick to a soft, bland diet.
- Use a Soft Toothbrush: Switch to a soft-bristled toothbrush and brush gently to avoid further irritating the ulcer.
- Over-the-Counter Topical Treatments: Pharmacies sell various gels, pastes, and protective pastes (like Kenalog or Bonjela) that create a barrier over the ulcer and contain mild anaesthetics to numb the pain.
- Antimicrobial Mouthwashes: Rinsing with a chlorhexidine mouthwash (available from your pharmacy) can help prevent the ulcer from becoming infected and promote healing.
When to See a Dentist About a Mouth Ulcer
While most ulcers are benign, you should never ignore a persistent lesion in your mouth. You must schedule an appointment with your dentist or doctor if you experience any of the following warning signs:
- The ulcer lasts longer than three weeks. This is the most critical warning sign. An ulcer that does not heal within 21 days must be professionally examined to rule out oral cancer.
- The ulcer is unusually large or spreading.
- The pain is severe and cannot be controlled with over-the-counter medication.
- You experience extreme difficulty drinking fluids.
- The ulcer is accompanied by a high fever or feeling generally unwell.
- You are developing new ulcers before the old ones heal.
- The ulcer is painless. (Painless ulcers that do not heal are a particular red flag for oral cancer).
How Your Dentist Can Help
If your mouth ulcer is caused by dental trauma—such as a sharp, broken tooth, a poorly fitting denture, or an irritating orthodontic wire—your dentist can quickly resolve the issue. By smoothing the sharp edge or adjusting the appliance, the source of the trauma is removed, allowing the ulcer to heal rapidly.
If the ulcer is persistent and the cause is not obvious, your dentist will perform a thorough examination. They may prescribe a stronger topical corticosteroid or an antimicrobial rinse. If they suspect the lesion is abnormal, they can perform a biopsy or refer you to an oral specialist for further investigation.
Do Not Ignore Persistent Mouth Ulcers
If you have a mouth ulcer that is causing you severe pain, is the result of a broken tooth, or has not healed after three weeks, do not wait.
Book a consultation at Your Family Dentist Liverpool or Blacktown — call us today. We will assess the ulcer, provide effective pain relief, and ensure your mouth is healthy and safe.