Tray whitening: Bleaching the teeth with Take-Home Trays is accomplished by wearing bleaching trays with bleaching gel in them. The trays will be made of thin clear flexible vinyl. Most patients find these trays very comfortable to wear and sleep with. You will be given a bleaching kit. This kit includes bleaching gel, fluoride, and a storage case for the bleaching trays. Whitening your teeth with the at-home bleaching trays is best done with a commitment of wearing trays to bed for at least 4-6 weeks.