Mouth Ulcers That Won't Heal: When to Get Checked

What is a mouth ulcer?

Mouth ulcers commonly referred to as canker sores are small sores that can develop on the soft tissues inside the mouth, including the inner cheeks, lips, tongue, gums, and the floor or roof of the mouth. They are common and, in most cases, resolve on their own within a week or two.

Many people experience mouth ulcers from time to time. They can be uncomfortable, particularly when eating, drinking, or speaking.

How long do mouth ulcers usually last?

Most mouth ulcers typically heal within 7-14 days. Minor ulcers typically do not leave any scarring and tend to resolve as the tissue repairs itself naturally.

A commonly referenced guideline in oral health is the two-week rule: a mouth ulcer or oral change that has not shown signs of healing within two weeks warrants professional assessment.

What changes might prompt a professional assessment?

There are several features an oral health professional may consider when assessing a mouth ulcer. These include, but are not limited to:

•        Duration beyond two weeks without improvement

•        A sore that appears to be growing in size

•        Changes in the colour or texture of the surrounding tissue

•        Persistent discomfort or altered sensation in or around the area

•        Sores that bleed without obvious cause

•        Difficulty with swallowing, chewing, or opening the mouth

This list is not exhaustive. Anyone concerned about a change in their mouth is encouraged to seek professional assessment rather than self-monitor indefinitely.

What conditions can cause persistent mouth ulcers?

There are many different reasons a mouth ulcer may be slow to heal or may recur. A qualified health professional is the appropriate person to assess and investigate these. Potential contributing factors may include nutritional considerations, inflammatory conditions, infections, reactions to medications, autoimmune disease or other systemic health factors.

A persistent or unusual sore in the mouth can, in some circumstances, be associated with more serious conditions. For this reason, professional assessment is generally recommended when the two-week guideline is reached, even in the absence of other concerning features.

What is oral medicine?

Oral medicine is a dental specialty that focuses on the diagnosis and non-surgical management of conditions affecting the mouth, jaw, salivary glands, and related structures. Oral medicine specialists have completed specialist training beyond general dentistry and see patients with a range of conditions including ulceration, oral mucosal disease, persistent pain, dry mouth, and other concerns that may require investigation.

Patients can be seen following a referral from their general dentist or general practitioner, or in some cases by direct appointment. A specialist assessment typically involves a detailed clinical history, thorough examination, and a discussion of any further investigations that may be appropriate.

General information about oral cancer awareness

Mouth cancer, also referred to as oral cancer, can develop in various parts of the mouth and throat. The Australian Dental Association and other public health organisations recommend regular dental check-ups as part of general oral cancer awareness, as early assessment of any unusual changes in the mouth is considered important.

For general information about oral cancer, the Australian Dental Association and Cancer Council Australia provide publicly available resources that may be of interest. This article does not provide advice specific to any individual situation.

When should someone seek professional advice?

Anyone concerned about a change in their mouth, including a sore, ulcer, patch, lump, or persistent discomfort, is encouraged to speak with their general dentist or general practitioner in the first instance. These practitioners can assess the concern and, where appropriate, refer on to an oral medicine specialist if necessary.

The two-week guideline exists as a practical prompt rather than a diagnostic tool. It is not a substitute for professional assessment, and individuals should not delay seeking advice if they are concerned, regardless of how long a change has been present.

IMPORTANT: This content is for general information purposes only. It does not constitute medical or dental advice. Readers should consult a qualified health professional regarding any personal health concerns.