What the dentist will do
If you put the tooth back in, the dentist will check it's in the right place and move it if they need to.
If you brought the tooth in milk or saliva, they will clean it and put it back in.
They will then fix the tooth to the teeth either side of it to hold it in place (splinting). You will probably need to go back after a couple of weeks to have the splint removed.
If you can't find the tooth, or the dentist's not able to save it, it can normally be replaced with a false tooth.
Read more about false teeth and other dental treatments.