Ulcer on inside lip
An ulcer inside the lip is often a shallow sore from trauma or a canker sore, but a persistent or unusual lesion needs examination.
The short answer
An ulcer inside the lip is usually a shallow inflamed break in the lining caused by local trauma or a canker sore, but a persistent or unusual lesion needs examination.
What is the direct answer?
What does this question mean?
The inside of the lip is lined by soft oral mucosa that can be injured by biting, a sharp tooth edge, braces, or a rough restoration. A canker sore is a non-contagious ulcer that typically has a pale base and a red border.
What can you do next?
Avoid biting or rubbing the area and choose softer, cooler foods while it heals. Use a soft toothbrush, keep the mouth clean, and ask a pharmacist or dentist about a suitable topical product if eating is painful.
When should you seek dental care?
Arrange an examination if the ulcer lasts longer than expected, repeatedly returns in the same place, enlarges, bleeds, feels firm, or is accompanied by a neck lump or difficulty swallowing. A dentist can check for a sharp tooth, appliance irritation, infection, or another mucosal condition.
What should you ask the dentist?
Ask whether a tooth, filling, denture, or orthodontic component is rubbing the sore. Ask what features would require follow-up and whether the lesion should be photographed or referred for further testing.
Frequently asked questions
Are ulcers inside the lip contagious?
A typical canker sore is not contagious. Sores caused by some viral infections have different appearances and may spread through contact.
Why does the ulcer keep coming back?
Repeated trauma, canker sores, irritation, and some medical conditions can cause recurrence. The pattern and examination help distinguish them.