I'm 26 years old, and got my braces 13 months ago and should have them taken off within 2 weeks. I had big spaces between my teeth. My ortho doesn't believe in permeant retainers and refuses to put them on his patients. I'm leaving the country in several months and would not be able to see him in case the spaces came back, so I want to get permeant retainers with any other ortho and wear the essix retainers which my current ortho will provide. Is that a good idea to keep teeth from moving?