They used to pull all of your wisdom teeth at the slightest hint of them being a problem. Now they won't do it unless you are getting repeated problems.

It's because of the nerve that passes very close to them, more-so on the bottom ones. This nerve is the sensory one, not the motor one. This means if they damage it as they are crow-barring your head, you may loose some of the sensitivity in your lip or something. It's hugely rare, and even rarer for it to last any more than a couple of weeks. There should be no way of you loosing the movement of anything though, so it's nothing to worry about.