A. The result varies from system to system & patient to patient. In general you can get similar results with a lot of systems if you have time. I prefer tray whitening when 1. the patient wants to match to existing crowns or veneers, 2. patient is worried about going too white before they have the chance to stop. 3. its often cheaper 4. its easier to manage tooth sensitivity I prefer power whitening such as Zoom! when 1. the patient has a deadline ( eg family wedding next week) 2. patient cant sleep with trays in 3. patient uncomfortable administering their own kit I prefer hybrid systems like “enlighten” when the patient wants the maximum result in the minimum time and is prepared to pay a little more. Hope this Helps Rob StJohns Dental practice in Birmingham is 1 minute from New Street station. We offer a free initial consultation for cosmetic cases. Call Amy on 0121 643 0610 for details or follow the weblink from CDG.