Brief Answer:
Can be canker sore, take multivitamin

Detailed Answer:
Hi

Thanks for writing in.

I would like to ask you questions:-
- since how long you have this problem?
- is it recurrent?
- is it single or in cluster?
- is it unilateral or bilateral?
- can you upload its picture?

There can be various reasons of canker sore:-
- stress is major cause
- trauma
- spicy food
- gastric problem.

First line of treatment is include multivitamin in your diet.
Apply anaesthetic gel on that region to relieve pain.
Normal ulcer heal within 1 week.
If it persists more than 3 weeks then consult your dentist.
Avoid spicy food.

Hope I answered your query

Wishing you good health

Regards
Dr. Neha Sumra

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