Most of the time these are caused by minor trauma damage but can also be caused by stress, tiredness, deficiencies in Vit b, folic acid and iron.
There are many other small print causes but these are the main ones.
If you do get an ulcer, first try a think if there was a cause; caught your cheek, crusty bread that sort of thing. If you can’t remember a cause then now you have to manage it.
Things like bongela and igloo and hot salt water mouthwashes are helpful but the main thing to remember is it will get better, try and steer away from acidic and spicy things as it will inflame an already swollen area. If it doesn’t resolve after a couple of weeks (sometimes it is worth making a note in a diary so you have a start date) then get either your dentist or doctor to take a look.
We advise that you contact your dentist for advice on your specific problem. Your dentist may ask you to take a picture of your ulcer and send it to them to review and advise you accordingly.