HK Dental Guide
Oral healthResearch news · 31 Aug 2026

Mouth ulcers: why they occur and how to ease them

A general-interest health article compiles medical explanations for mouth ulcers, noting up to a quarter of people experience them at some point, especially teenagers and young adults, with most healing within one to two weeks. It lists common triggers such as trauma, certain foods, stress, hormonal changes, nutrient deficiencies and smoking cessation, alongside remedies like saltwater rinses, topical anaesthetic gels and antiseptic mouthwash.

What it means for you

This kind of article helps readers distinguish ordinary mouth ulcers from warning signs that need medical attention, such as an ulcer lasting more than three weeks, recurring frequently, or looking unusual, so they do not overlook rarer but serious causes like oral cancer.

Editors' take: the background

An ulcer that has not healed after two weeks, keeps coming back often, or comes with fever or difficulty swallowing should be checked by a doctor or dentist rather than treated with over-the-counter gels alone. Using a soft-bristled toothbrush and avoiding scratches to the mouth can also reduce irritation.

If certain foods or nutrient deficiencies are suspected triggers, keeping a food diary and asking a family doctor about a blood test can help identify the cause, rather than self-diagnosing.

Key points

  • Most mouth ulcers heal within one to two weeks; saltwater rinses and topical anaesthetic gels can ease discomfort
  • Common triggers include biting the cheek, toothbrush injury, spicy or acidic foods, stress and early smoking cessation
  • If an ulcer lasts more than three weeks, keeps recurring, or looks unusual, seek medical checkup promptly

Source: The Conversation

This is a news summary written by our editors, not medical advice. Please refer to the original source and seek professional advice for your own situation.

Questions readers ask

Are mouth ulcers contagious?

No, ordinary mouth ulcers are not contagious, unlike cold sores which are caused by a virus.

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