A baby (primary) tooth that is knocked out will not be replaced, as it could cause damage to the developing tooth underneath. In certain cases, a space maintainer may need to be placed to ensure there is room for the adult tooth to erupt. When an adult (permanent) tooth is knocked out, we do our best to save it. It is important to try and place the tooth back in the socket immediately if you can, otherwise call your dentist or go to an emergency room as quickly as possible to give the tooth the best chance of survival.