As the name implies, Invisalign clear aligners are made of almost invisible polyurethane plastic. Rather than being cemented or bonded to the teeth as metal or clear braces are, clear aligners are completely removable — for important social occasions, for eating, and, most importantly, for tooth-brushing and flossing. This advantage can also be a disadvantage: It means you must resist the temptation to take your aligners out more than is advised. Here are some other advantages of the Invisalign system: 
- Improved Oral Hygiene — With an orthodontic appliance that is removable, you will be able to clean your teeth much more easily than if you were wearing metal braces.
- A Discreet Look — If you consider your orthodontic treatment to be a private matter, or simply feel that metal braces don't fit with your self-image, a practically invisible form of orthodontic treatment might suit you.
- More Dietary Choices — To protect metal wires and braces, some diet modifications are necessary. With clear aligners, you can still bite into an apple or a crispy pizza crust.
- Comfort — The thin, flexible material of which Invisalign is made will not irritate the soft tissues of the mouth, as metal wires and braces can.
- Teeth-Grinding Protection — If you have a teeth-grinding or clenching habit, clear aligners can function as thin nightguards that will protect your teeth from excessive wear.
Clear aligner technology has been improving over the years and can correct many malocclusions that once would have been too complicated for this form of treatment. Yet there are still some situations for which traditional braces would still be best. This can be discussed in detail with you.
How Invisalign Works
Invisalign 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 Invisalign 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.
Caring for Your Teeth During Invisalign Treatment
As mentioned above, one of the main advantages of the Invisalign system is that the trays can be removed for easy cleaning. So please don't neglect to do this! You'll need to brush your teeth after every meal or snack so that food and plaque do not get trapped in the aligners, which could promote tooth decay and gum disease. Your aligners, too, will have to be cleaned regularly; you can do this by brushing them and then rinsing them with lukewarm water.
Also, please keep in mind that while wearing clear aligners is very different from wearing braces, the importance of retaining your post-treatment results is exactly the same. You'll want to be sure to wear your retainer(s) exactly as prescribed after your treatment is completed to protect your investment in a beautiful new smile.