When to worry about a persistent mouth sore with mouth cancer

A mouth cancer sore may appear on the tongue, gums, cheek lining, palate, or floor of the mouth. It can be painful or painless and may look like an ulcer, rough patch, or area of thickened tissue. Dental trauma, infection, irritation from a sharp tooth, and other conditions can also delay healing, so appearance alone cannot establish the cause.

Book an assessment with a dentist, doctor, or oral and maxillofacial specialist if the sore is not settling or keeps returning. Record when it began, its location, changes in size or colour, bleeding, and possible irritation from teeth, dentures, or food. Avoid tobacco and alcohol, do not pick the area, and follow any advice for gentle mouth care.

Seek prompt care for a sore with persistent bleeding, a hard edge, increasing pain, altered sensation, loose teeth, a neck lump, or difficulty chewing, speaking, or swallowing. Get urgent help if swelling affects breathing or swallowing, or if bleeding is heavy and does not stop with gentle pressure. Do not wait for severe pain before arranging review.

Ask whether the sore needs examination by a dental or specialist team, whether an irritating tooth or denture could be involved, and whether a biopsy is appropriate. Mention tobacco, alcohol, medicines, recent dental work, weight change, and any numbness or neck swelling. Ask how soon the area should be reassessed if it remains unchanged.