Which is the best tray material to use for teeth whitening?

off label, you can use your invisalign trays for whitening but you have to be a lot more conservative with the amount of gel you place in them. i generally don't recommend it. when custom whitening trays are made, they are allowed space for the gel so it wouldn't ooz out and harm your gums. the most important thing in home whitening is to make sure you keep the get away from your gums and areas on your teeth where you have recessions of your gums (if any).  also be sure you don't have any cavities, the gel can really harm a tooth that has a cavity.

Your dentist can fabricate a custom fit set of whitening trays after taking impressions of your teeth. These trays will then be used by you at home with a lower percentage of whitening gel that you will place into the trays and wear for 4-5 hours (depending on the product). The material that is used for whitening trays is different to each doctor, but most of the time the tray material is a thin clear plastic.If you have Invisalign trays, you absolutely can use these for whitening your teeth. You will just need to purchase the whitening gel from your dental office. Keep in mind that your Invisalign trays are not scalloped along the tooth/gumline like custom fit whitening trays and less gel is better to avoid excess gel on your gums causing inflammation and discomfort. Drink lot's of water leading up to you whitening your teeth, along with starting a toothpaste for sensitivity. Continue water and toothpaste during and after whitening to help aide in tooth sensitivity. Rule of thumb ~ When eating and drinking foods that are colored with dyes have the potential to stain your teeth. If you are unable to brush your teeth immediately, rinse with water.