You may be tempted to buy over-the-counter teeth whitening kits, given their proliferation expecially on the Internet. Not only are they not made to fit your mouth exactly, it may be that bleaching isn't suitable for you, especially if you have gum disease or crowns. If your teeth are healthy and somewhat white, you may get a boost from such over-the-counter products, but again, they will not last long. The only home bleaching kits you should be using are the ones recommended by your dentist. The most important thing to look for in over-the-counter kits is that they fit the size and shape of your teeth. For example, whitening strips are straight across, while your teeth are curved. In addition, make sure that the at-home bleaching kits cover your whole tooth - otherwise you will have two toned teeth or irritated gums.
Professional tooth whitening from a dentist is always recommended. Your dentist will check for gum diseases, as well as loose fillings. She will be able to fit you for trays as well. In addition, she can monitor your teeth's response to the product - especially the reaction to your gums. A combination of in-office and at-home dentist prescribed whitening treatment will give you faster and longer-lasting results. It can provide maximum whitening with minimal effort and time while ensuring safety and effectiveness.