Since Invisalign was introduced to the public, over 15 million people have had their smiles transformed by this innovative treatment. This number includes over four million teenagers. Invisalign sets itself apart from other clear aligner treatments thanks to its patented SmartTrack material used to make the aligners. Your teeth will be moved in a comfortable manner that is easy to predict and track. All aligners and retainers offered by Invisalign are made of medical-grade thermoplastic polymers. These materials were chosen for their safety and because they are FDA-approved.