For extreme cases of discolored set of teeth, the porcelain veneer can be used as well. When used and fitted the way, these veneers can promise longevity and will surely enhance the smile and the whiteness of the teeth. Another complementary role of the veneers is that its use can help protect the surface of the tooth. The results can be realized after a few days, and the white color of the teeth can be maintained for months provided of course that proper maintenance is made. The strips on the other hand are thin strips that are coated with the gel fortified by hydrogen peroxide. These strips are also attached to the teeth twice a day. Even as professionally supervised teeth whitening treatments contain hydrogen peroxide as its active bleaching agent that is safe enough even for home use, over the counter preparations contain carbamide peroxide which is even safer and milder. The effects are the same. While hydrogen peroxide acts faster, carbamide peroxide when left in the mouth for a time divides into urea and hydrogen peroxide that acts on the stains by the oxidation process. This gel in question contains peroxide in just the right quantity that can ensure that the teeth will whiten. And since this is the laser whitening procedure, expect that light will be used as well and this is used to activate the gel. The whole procedure will go on for an hour and could whiten the teeth by as much as 10 shades. It could shade darker as the person grows older, perfectly normal. While the darkening of the teeth as it ages is mainly due to the changes in the teeth's mineral structure, the enamel at the same time gets less porous and less shiny making it more susceptible to stains from bacterial pigments, medication, tobacco, wine, coffee, tea and food. Unlike tooth whitening done at home, in-office whitening is conducted and monitored by a professional practitioner. Risks therefore, no matter how low and the aftereffects no matter how mild is attended too eliminating discomfort. Not everyone is a good candidate for in-office teeth whitening. People with tooth and gums hypersensitivity may undergo a different regimen or may be given home treatment kits for the patient to use though due to the patients hypersensitivity, the treatments and dosages are mild and will therefore take a longer period of time.