Retainers do exactly what they say they do, "retain" or hold the teeth in their corrected positions. I'm not sure why one would go through the process and cost of correcting one's teeth and not follow their orthodontist's instructions of wearing the post treatment retainers. Before you try to "jam" the retainers in the mouth, its very important to make a follow up appointment with your orthodontist to re-evaluate your teeth and determine IF the current retainers fit or can be adjusted. With minor tooth movement and tight retainers, wearing them 24/7 for a determined time may move them back into place. Only an orthodontist can determine that. If the teeth have moved to a point where the current retainers do not fit, clear aligner therapy is an option (Clear Correct, Invisalign, etc..) There are other types of removable spring loaded retainers that can also move teeth. Again, before you do anything, PLEASE make a follow up appointment with your orthodontist.