I've flown the day after having a tooth out and a dental implant put in, and had no pain at all. I've also flown the day after fillings, permanent and temporary, after root canals and didn't have a problem. I know airlines have various rules about not flying within so many days of treatment, but for me it was either fly or go sick, and face the consequences! I chose to fly. Of course we are all different, and I'd just be concerned about your insurance cover if you are going on holiday, and you develop pain after your dental treatment, whilst away. As I say, I had no pain, but best check if you are covered with your insurance should anything go wrong.