I upped the quantity of salt and baking soda in my mouth rinse and Dr Bufi was right -- if it stings a little, it means it's working! My mouth sore definitely began to heal as soon as I changed the formula.
3 teaspoons coarse (kosher) salt
2 tablespoons baking soda
I used hot water to dissolve the salt and baking soda and then filled a container with cool water to make 12 ounces of solution total. I use it at least 3-4 times a day.
This is about one week's worth of mouth rinse for me.