Bacteria can help these ulcers along, too. I have Crohn's and can get mouth ulcers...canker sores. I use straight rum. I swish it around in my mouth and spit it out and repeat it about 12 hours later. It will burn like a son of a gun and then your mouth will feel numb for a few minutes. The canker sores start feeling better in a few hours. The second time you do this, it doesn't burn nearly as much. I usually do this for several days until they are all gone.
Fishchris was having a big problem with this and tried everything. I told him what I did, he tried it, and it cleared up the sores.
Sherrine