The short explanation
Yes, a mouth ulcer that has not healed in more than three weeks should be checked by a doctor or dentist, even if you do not use tobacco. Most ulcers heal within one to two weeks. Long-lasting ones are often caused by a sharp tooth, a rough filling or ill-fitting denture rubbing the same spot, or by conditions such as vitamin deficiencies or gut problems. Mouth cancer is much less common in people who do not use tobacco, alcohol or areca nut, but it can still happen. An examination helps find the cause and, if needed, a small sample can be taken to be sure.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Red or white patches, a lump, numbness, difficulty swallowing or loose teeth without reason are also worth reporting.
- Frequent ulcers that come and go can be linked to stress, low iron, B12 or folate, or some medical conditions.
- Dentists are good at spotting mouth changes; regular dental check-ups help.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot tell you what is causing your ulcer. An examination is needed.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- What is causing this ulcer?
- Could a tooth or filling be rubbing it?
- Do I need a biopsy?
- Should my blood be checked for vitamin deficiencies?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Book an appointment soon
- See a doctor or dentist within a week or two for an ulcer that has lasted more than three weeks.
Raise it at a routine appointment
- Book regular dental check-ups.
Sources
The evidence this explanation is built on.
- Mouth ulcers NHS
- Mouth cancer NHS
- Oral cancer MedlinePlus (US National Library of Medicine)
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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