Mouth ulcers: when to see a dentist
Quick answer
How long do mouth ulcers last, and when should I see a dentist?
Most mouth ulcers heal on their own within 7–14 days.
See a dentist if an ulcer lasts longer than three weeks, keeps returning, grows, or arrives with a lump, numbness, unexplained bleeding or difficulty swallowing — those are the red-flag signs for mouth cancer, which is highly treatable caught early. An examination at York House Dental Practice in West Byfleet costs £52; urgent problems are seen from £78.
What causes mouth ulcers?
The common causes are mechanical (biting your cheek, a sharp tooth edge, an ill-fitting denture rubbing) and systemic: stress, disturbed sleep, low iron, B12 or folate, and hormonal changes all trigger aphthous ulcers in susceptible people. Switching to a toothpaste without sodium lauryl sulfate helps some. Traumatic ulcers heal once the cause is smoothed or adjusted — a fifteen-minute dental fix.
How do you look after a mouth ulcer at home?
While it heals: a soft brush, cool plain food, and a pharmacy gel or antiseptic mouthwash for the pain. Avoid spicy, acidic and very salty food, and keep the area clean rather than smothered in numbing gels all day. An ulcer that is clearly improving day on day is behaving normally.
When should you worry about a mouth ulcer?
The three-week rule exists because more than 8,000 new mouth cancer cases are diagnosed in the UK each year and numbers are rising, with early detection making treatment dramatically more successful. Dentists screen your whole mouth at every examination — it is part of the £52 check-up. Ulcers under a denture that never settle should prompt a denture review; see dentures at York House.
Care at York House Dental Practice
Welcoming new patients, families and emergency appointments from West Byfleet, Woking, Weybridge, and across Surrey.
Last reviewed: by Dr Kaveet Patel, Principal Dentist
