Application of a light or laser does not speed or increase the bleaching of teeth beyond the use of bleaching chemicals alone. The active ingredient in most teeth bleaching products is Hydrogen Peroxide. Over the counter products (OTC) generally contain lower concentrations of bleaching agents and may take longer to achieve results. Professional products that are applied in a Dental Office can contain higher concentrations of Hydrogen Peroxide which may require professional supervision and protection of gingiva (gums) and mucosa from irritation and burn of the stronger peroxide agents. Professional Products work faster but may cause more tooth sensitivity than weaker concentrations of bleach. The application of a light or heat does not appear to enhance the overall bleaching effect. Take home professional products with the use of custom made trays can achieve quicker results than over the counter products and the bleaching agents can be applied more effectively to the target teeth to be lightened. It is important to have your teeth examined by a Dentist before considering bleaching by any method. The Dentist can advise you if have any Dental Disease that should be corrected prior to bleaching and if your teeth are a good candidate for bleaching. Dental restorations will not bleach with Hydrogen Peroxide so you need to discuss with your Dentist whether these restorations should be replaced after bleaching to match the lighter shade of your teeth. When you receive a Professional Bleach in Office and your teeth are isolated and exposed to bleach you may notice an immediate whitening effect from dehydration of the teeth which may reverse when the teeth re-hydrate over the next couple of weeks. So the real bleaching effect can not be measured until this happens. Also it is important to not have any bonded restorations placed for at least a couple of weeks after bleaching to prevent inhibition of the set of the bonding agents by oxygen from the bleaching agents and you also want the shade to be an accurate match. Discuss with your Dentist if you have been bleaching your teeth before you have any restorative treatment performed.