I have a sore near my gum which keeps bursting and then coming back. This happens about twice a week. The dr. has given me anti.bios and a mouth wash but neither work. It isn't what I would call an ulcer and it doesn't hurt - it's more like a blister or a 'spot'. Sorry to be so graphic but I have had it for weeks. I am under a lot of stress at the moment and dr. thought this might have something to do with it. Has anyone else had this problem?