The Zoom whitening system consists of a high-concentration bleaching gel (a.k.a. hydrogen peroxide) and an ultraviolet light. The UV light accelerates the bleaching process and helps the hydrogen peroxide penetrate your teeth. The gel is applied for three 15-minute sessions for a total treatment time of 45 minutes.
Zoom whitening hurts like a motherfucker, which is why at-home whitening systems are still available. Custom-molded trays filled with dentist-dispensed gel are worn 1-2 hours a day for up to 14 days. Tooth sensitivity is less severe and should subside after a couple of days.