Getting rid of canker sores?

My roommate used to have a major problem with this and he used to do two things. I never observed whether they actually worked, but if you are desperate and can't deal with it anymore then do this. The first thing he used to do was use mouth wash constantly. Now the only reason I can think of to do this is to remove any bacteria present on the sore while trying to keep the sore clean and allow healing to take place. The other thing that he used to do was put toothpaste on them, but the fact that they are on your tongue I would warrant against putting too much because it is not healthy to ingest toothpaste.