[url=http://modernagedentistry.com/]Invisalign[/url]� is a relatively new type of orthodontics, involving no metal at all. Instead of wiring up each tooth, the patient is provided with clear plastic aligners. If you are familiar with teeth whitening trays, these aligners will be familiar to you. They slip over your teeth and gently persuade them to move gradually into a better position, over time.