Hi sir.....
Mouth ulcer may be due to many cause.....It may be due to stress,
vitamin deficiency,or due to irritation from any sharp tooth,burns from hot and spicy food ,sometimes gatric disturbance may also cause mouth ulcer...
Next Steps
Kindly visit nearby dentist to rule out the cause and treatment should be done according to that
Health Tips
Avoid self medication and avoid eating hot and spicy food items....consume plenty of water..