hello and welcome to HCM forum,
i would be glad to answer your query, first of all i would like to inform you that an oral ulcer
can develop due to any of the following causes, vitamin deficiency
, medical condition, poor oral hygiene
, spicy food or even due to constant irritation from a sharp tooth margin or a filling.
i cannot rule out the cause for you until your oral cavity is checked clinically.
therefore, it would be best see a dentist
, he /she will rule out the cause and plan a treatment accordingly.
In cases with recurrent oral ulcers it is very important to remove the cause permanently.
i would recommend a few instructions for you to follow;
1. use an antibacterial mouth wash(twice/day) for 1 week,
2. healthy diet,
3. avoid spicy food for a few days,
4. visit your dentist soon.
i hope i answered your query,
i wish you good health,