If you should loose a tooth filling, call to get into a dentist at the soonest available time. In the meanwhile, here are a couple of short-term remedies. Inquire at your pharmacy about an over-the-counter dental cement to use as a temporary stop gap. Or, a piece of sugar-free gum can also be applied into the cavity until you see your dentist. Just be sure that gum is sugarless as even a little sugar in a cavity will hurt!