How Far Back Will It Set my Treatment to Have the Aligners in for Less Hours for a Week?

Obviously, you should try to wear the aligners as many hours as possible while you are on vacation, espcially all night long while you are sleeping. If you do wear them at least a few hours every day, you will probably only have to extend wearing the same set of aligners for an extra week or 2, assuming the vacation is only a week. Do not go to your next set of aligners as originally scheduled (usually every 2 weeks).

You should wear your aligners 23 hours a day.  There is a great tendency for rebound in orthodontics.    If you leave them out for extended periods the teeth move all the way back to where they were.  The ligament stretches and rebounds.  THere has to be constant pressure to get the biomechanical results you want which are break down of the old ligament, replacement with the new ligament and new bone formation.  See google images for a description of the periodontal ligament to which i am referring.