If a tooth is avulsed (knocked out), make sure it is a permanent tooth (primary teeth should not be replanted).
Keep the patient calm.
Find the tooth and pick it up by the crown (the white part). Avoid touching the root.
If the tooth is dirty, wash it briefly (10 seconds) under cold running water and reposition it. Try to encourage the patient / parent to replant the tooth. Bite on a handkerchief to hold it in position.
If this is not possible, place the tooth in a suitable storage medium, e.g. a glass of milk or a special storage media for avulsed teeth if available. The tooth can also be transported in the mouth, keeping it between the molars and the inside of the cheek. Avoid storage in water.
Seek emergency dental treatment immediately.
For all other types of fractuce or trauma to the teeth seek immediate dental treatment. Apply a cold compress to the area in the meantime to reduce swelling as this can furthur damage the teeth.