How do you decide if something is a true dental emergency? Generally, if you have swelling, an exposed tooth, bleeding, or sharp throbbing pain, that is a dental emergency. If you knock a tooth loose or out, attempt to gently rinse it off lightly with water and reposition it as soon as possible. A tooth that is knocked out and let dry in the air for over an hour has a poor prognosis, whereas a tooth that is reimplanted within twenty minutes, has a good prognosis. If you have spontaneous ongoing pain or swelling or have experienced trauma, you should make arrangements to see your dentist as soon as possible. CDA