Local anaesthetic if you can (depends on circs of course and how many you need out and where; if on opposite sites and need doing at the same time you will require general anaesthetic)
Usually no big problem but if the ones in the top of your jaw are solidly fixed and the roof is thin you may get a sinus perforation.
For that reason prob good idea to mention to the max-fax or dentist that you fly so they check for airleaks.