Whitening agents actually change the color of your teeth, but only are effective on certain types of stains. For example, bleaching agents have a difficult time removing brownish or grayish stains. These products also are not as effective on pitted or badly discolored teeth, or on restorations such as crowns, bridges, bonding and tooth-colored fillings (porcelain veneers or dental bonding may be more appropriate in this case).
Professional whitening performed by our office is considered to be the most effective and safest method; done properly, tooth whitening can last as long as five years. Over-the-counter whitening systems are somewhat effective as long as they are monitored and directions followed closely.