it depends are they cutting your mouth or is your mouth soar? because you just got them on or changed? tylenol should help if you just got them changed (btw next time you get them changed take tylenol ahead of time) and ask your dentist for wax if they are cutting your mouth...but when it comes down to it like connor said just suck it up, it won't last long :D
Rinse your mouth with warm salt water. Using table salt is fine. As others have already posted, Tylenol will definitely help. But absolutely do not have any cold beverages, they will make the metal extremely more irritating to your inner cheeks and will make your gums mildly sore-er. If that's a word. Tylenol and rinsing with salt water!
Take some Tylenol, eat something cold and suck it up. It'll be over in a few days.