Your child just fell riding his bicycle. There is lots of blood. His mouth is a mess. Who do you call? What do you do? Children will find a way to injure themselves despite our best preventive measures as parents. Some oral-facial injuries are serious and some are nothing to worry about. How do you tell? Well, here are some guidelines.
If there is lots of blood, don't panic. Any injury to the mouth bleeds a lot. Check out the situation; hold a cloth (if you can) with pressure to slow the bleeding. Most bleeding stops within 10 -15 minutes whether you do anything or not. Once your heart stops racing so much, look and see what the problem is. First look and see if there are facial cuts or lacerations, fear of a broken jaw, possible head trauma causing loss of consciousness (concussion), multiple knocked out and displaced teeth (an oral surgeon may need to see you at the hospital), or if you just are not too sure, then you need to go to the ER. They can stitch up any facial lacerations and take major X-Rays to check all that other stuff.
Now, if you don't have those bad things, you still might have a scary mess to deal with. If you go to the ER, you are likely to sit there for many hours and then they will call your dentist anyways. You can call your dentist first and he/she may be able to save you the trip to the ER.
If there is a broken tooth, the ER is not likely to be able to do much. If a tooth is knocked out, and if it is a permanent tooth, you need to get the tooth back in soon as possible, your dentist can help. The ER can put a knocked out tooth back in too, but you still may need a dentist to splint the tooth, so you may want to call the dentist first. If the knocked out tooth is a baby tooth, just leave it out and put it under their pillow. A baby tooth can be intruded (pushed up into the gums) where is difficult to see. Sometimes it can re-erupt on its own, but still may need to be removed or need other longer term treatments.