Canker sore bottom of mouth
A canker sore on the floor of the mouth is a shallow ulcer in the movable lining beside or beneath the tongue, usually tender and not contagious.
What is a canker sore on the mouth floor?
A canker sore on the floor of the mouth is a shallow ulcer in the movable lining beside or beneath the tongue, usually tender and not contagious.
What can irritation mean when an ulcer keeps returning?
It may follow minor trauma or irritation, and recurrent or persistent ulcers need assessment for other causes.
How can you protect an ulcer on the mouth floor?
Avoid spicy, acidic or sharp foods, use a soft brush and rinse gently with salt water; do not scrape or burn the ulcer.
When should an ulcer on the mouth floor be assessed?
A dentist inspects its size, edge, colour and location, checks nearby teeth and asks about recurrence, medicines and other symptoms.
What should you ask about a persistent mouth-floor ulcer?
Seek care if it lasts beyond two weeks, keeps returning, enlarges, hardens, bleeds without trauma or comes with a neck lump or swallowing difficulty.
Frequently asked questions
Can this be handled at home?
Avoid spicy, acidic or sharp foods, use a soft brush and rinse gently with salt water; do not scrape or burn the ulcer.
What will a dentist check?
Seek care if it lasts beyond two weeks, keeps returning, enlarges, hardens, bleeds without trauma or comes with a neck lump or swallowing difficulty.
Who wrote this page
This library is published by Dental Nation, a licensed dental group practising in the United Arab Emirates. Pages are written and overseen by the same clinical team that treats patients in our clinics, and are held to a fixed editorial standard for safety and accuracy.
This page is patient education, not medical advice, and cannot replace an examination. Anything urgent — facial swelling, trauma, uncontrolled bleeding or severe pain — needs a dentist or emergency care now.