Remedy for a tooth ache?

It’s 2 am right now so he can’t go anywhere for it right now. My so woke up to tooth pain, I guess he had a cavity and the tooth like broke in his sleep and he’s in excruciating pain and is actually crying which is really weird I’ve never seen him cry over anything? I want to help him but right now I don’t know how. He plans to call the dentist when they’re open.