Absolutely! If you have RA in your jaw joints, anything that requires you to keep your mouth open for a long time or put stress on the jaw by pressure or biting into something hard can cause pain that will take a while to heal. The next time you go to the dentist, take some painkillers before you go and ask them to use the pick tool attached to the drill instead of doing the scaling by hand - it's much faster and doesn't put as much stress on your jaw. If you jaw still hurts, take a couple of days of eating softer foods that can be cut into small pieces and if things are really bad, chewing with your front teeth instead of your molars is easier.