I woke up while having my wisdom teeth removed.
I remember my head being jerked, hearing a really loud crunch, groaning, and then the dentist said "oh shit.."
I presumed they then turned up the anesthesia and knocked me back out.  
My hand shook when I read that.
I save my serious dentistry work for when I have FSA dollars left at the end of the year.  It's an incentive to keep solid records and not waste pre-tax dollars...
I didn't feel a thing.  Was so numbed up and out of it.  Thankfully.
This was a long time back, and I remember being told there were two ways to remove wisdom teeth:  They either cut them out, real surgical like, or they cut into your gums just enough to grab the tooth and crush it, then just pick the pieces out.  Beforehand, I never asked my dentist which method he was using on me; but I still found out.  That was the worst part of it.
All the awesome drugs for days was the best part.