Dental emergencies are where the American system fails most visibly: the emergency room will see anyone, but it usually cannot treat a tooth. Knowing which door to walk through saves both the bill and the second trip.

When to go to an emergency room, not a dentist

A dental infection can move beyond the tooth and become life-threatening, and a facial or jaw injury can need treatment the same day. If you think what you have might be an emergency, go to an emergency room or call emergency services. That judgment needs a person rather than a web page, and it is one of the very few situations in dentistry where the price of the visit should not enter the decision at all. If you want to talk to someone before deciding, many insurers, state Medicaid programs and health centers run a nurse advice line.

What an emergency room can and cannot do

Most hospital emergency rooms do not have a dentist on staff. What they can reliably do is assess whether the infection is dangerous, prescribe antibiotics, provide pain relief, drain a serious abscess, and admit you if you need it. What they generally cannot do is extract the tooth, fill it, or perform a root canal. This matters financially: an emergency room visit for toothache is expensive and usually ends with you still needing a dentist. If the problem is a painful tooth without the danger signs above, a dental clinic is both cheaper and more likely to actually solve it.

Getting seen quickly at a low-cost clinic

Many community health centers hold same-day or walk-in slots for dental emergencies and do not advertise them. When you call, do not ask for the next available appointment -- say that you are in pain and ask whether they have an emergency or walk-in slot today. Call early in the morning, when those slots are released, and call more than one location of the same organization. If a clinic cannot see you, ask them who they refer emergencies to; they generally know the local picture better than any search result. Dental schools also run urgent care or emergency clinics, though these usually operate on set days and screen before treating.

A knocked-out permanent tooth is a race

If an adult tooth is knocked completely out, the chance of saving it drops sharply after the first hour. Pick it up by the crown, never the root. If it is dirty, rinse it briefly in milk or saline -- not by scrubbing, and not under a running tap for long. If you can, put it straight back into the socket and bite gently on a cloth to hold it. If you cannot, keep it in milk, or in the mouth between cheek and gum, and get to a dentist or emergency room immediately. Do not let it dry out, and do not store it in tap water. A baby tooth is not replanted, so for a young child the priority is stopping the bleeding and being seen, not saving the tooth.

Getting through the night

If you have an appointment tomorrow and need to survive tonight: over-the-counter pain relief taken at the correct dose is more effective than most people expect, and a combination of ibuprofen and acetaminophen is commonly recommended by dentists for dental pain provided both are safe for you. Sleeping with your head raised reduces the throbbing. A cold compress against the cheek helps swelling. Do not hold aspirin against the gum -- it burns the tissue and does not help the tooth. Heat on a swollen face can make an infection worse. None of this treats the cause, and pain that is controlled is still an infection that needs seeing.