Customers use the plastic strips while watching television, working out, doing household chores or overnight. The usual active bleaching ingredient is carbamide peroxide. Some strips uses hydrogen peroxide but only with 6% strength where normal concentration ranges from 10 to 20%. Since carbamide peroxide is only half the strength of hydrogen peroxide, the visible effect will take about two weeks of continued use, much longer than bleaching trays that contains hydrogen peroxide and in-office treatments but because it is, teeth whitening strips is gentle and comfortable to even those with very sensitive teeth and gums. These products are often marketed not just to correct uneven tooth alignment but these veneers are also looked at as something that can whiten your teeth. Originally, these veneers are used on the surface of the tooth in order to correct uneven teeth. And these products as well are used to cover misalignment of the teeth. And everyone can even increase the chance of being in the safe side if they can shop for the whitening tooth paste that is approved by the American Dental Association. And if you are one of those who will try this product for the first time due to its efficacy and safety, there are some things to note and to remember. And these products will always contain chemicals. And it is the role of these chemicals to break down the stains taken down by the abrasives. Half of the reason why this product works can be linked to the proper use and application. It is recommended by oral health practitioners that this should be used twice a day. Though there may be some services that will fall under $500, but be reminded that these services rarely come. In many of these services, the most common method that is used is the light therapy. This therapy makes the bleaching process faster and more effective. It is said that this process can lighten the shade of the teeth 10 times more than other whitening agents. It is an accepted fact that the over the counter medications and formulations will contain less concentration of the bleaching agent. In many products, the concentration will only reach up to 10 percent. For the formulation that are used by the professionals that conduct supervised teeth whitening procedures, the formulation for the peroxide may reach up to 43 percent and the strength of the bleaching agent will depend on the service provider.