Clear aligners work the same way traditional braces do: by applying carefully controlled forces to teeth to move them into a better position. But they are not made of metal; instead, they are made of clear, flexible plastic.

Here’s how it works: Specialized computer software is used to design a plan for moving your teeth from their current positions into the best possible alignment. This movement will be broken down into perhaps several dozen stages. For each stage, the clear aligners company will manufacture two plastic mouth “trays” or “aligners,” one to fit over your top teeth and one for the bottom. You will wear this first set of trays for two weeks, for a minimum of 20 hours per day. You will then move on to the next set of aligners in your series to accomplish the next stage of gradual movement. You will keep doing this until your teeth are correctly aligned.

In the past several years, two features have been added to make clear aligners a more appropriate orthodontic treatment method for teenagers. Special “eruption tabs” hold the appropriate amount of space open for molars that have not fully grown in. Clear aligners for teens also come with “compliance indicators” built into the aligner material, which fade with wear. This allows parents, dentists, and the teens themselves, to make sure the trays are being worn as prescribed. Treatment with Invisalign can only be successful if this is the case.