Teeth affect bands are pretty effective in closing gaps naturally if you use them properly. Once the gap is closed, its a good idea to wear a band a few nights a week to retain the results and get another Essix (plastic) retainer made or wire put on the back of the teeth so they don’t move again. Unless your retainer shape has warped (by breaking it or washing it in hot water or leaving in sunlight) your teeth shouldn’t have moved. You need to wear it at least 3 times a week for life to ensure minimal relapses. Once the teeth have moved, it will take more work to put it right so you might as well get into the habit of popping it in your mouth 3 times a week for an easier life. If you can clean your teeth 2x a day without thinking, so can putting in a retainer 3 x a week!