why didn't the dentist lose his license?

Is anyone familiar with the appropriately named Jackass films? These films are vignettes of a crew of guys, headed by Johnny Knoxville, playing practical jokes and pranks on each other, or doing distasteful things on dares. A few examples?

• One guy ate horse manure on a dare.
• A couple guys were tricked into getting into a limousine. Once they were in, the doors were locked and bees were poured in through the moonroof.
• One guy allowed himself to be branded on the backside (with a red hot brand shaped like a penis.

 You get the idea.

These don't interest me, but I have, unfortunately, seen a bunch of these stunts and pranks. Which is a bunch more than I need. But I learned something today that has me wondering. In one incident, a member of the crew was convinced to have his tooth pulled by a Lamborghini. That is, they tied it to the back of a car and had the driver burn rubber. In order to convince him to allow this, they paid a dentist to tell him the tooth was infected and needed to be pulled.

How is that not a violation of medical ethics? How come that dentist hasn't been censured?

The relevant video is below. But it is definitely NSFL.