Let me tell you something. Canker sores are the opposite of what is good. Because of these crappy things, I must numb my gums with benzocaine. I am not very good at it, despite having years of practice. Consequently, my lower lip, having been numbed in exactly the same pattern as Queen Amidala's lipstick, is now completely pain-free! Which is great, considering I had no pain there at all! Grr. I want to live the rainforest.