Seth does his mind thing.  He doesn't have to go far to find someone who knows who the dentist is.  You do.

It's the guy from the kendo match.  The one who was shot in his car.  That guy.  He's the one who did the filling on this old man.

Shit.

To Saul and my parents: "Well now what? Do we toss the clinic? How can we trace this connection?"

To the Toothbearer: "Look, man, you've got a radio transmitter in a filling and it's controlling some terrorists' explosives. I believe you, but the police won't, and you'll be in solitary faster than you can say 'I'm innocent.'"