Tooth whitening trays are the items in a tooth whitening kit that keep the gel in place. These trays fit just like a mouthpiece. The most effective ones are custom made or molded to your teeth. The better it fits around the curves of your teeth, the more thorough the whitening solution will be.
You are going to need tooth whitening trays for both your upper and lower teeth. They are separate in most kits so that you can apply the bleaching gel more efficiently. The trays are what keep the gel placed firmly against your teeth so the bleach can get your entire set of teeth.
Three Types of Tooth Whitening Trays
There are three basic types of tooth whitening trays. The first is the custom made tray. This is made by your dentist. If you ever get your teeth professionally whitened, you should end up with one of these. They are the best trays you can get as they are molded tightly to your teeth.
The next two types of trays are the ones that you find in the at home kits. The more effective tray is the boil and bite tray. It will conform to your teeth and be as close to a custom made tray as possible. The last type is just a general tray. It is like a one size fits all, but works well with the gel it comes with. Trays are an important part of the bleaching process. You should definitely look into a system that requires trays so you know you are getting a quality product.