how much hydrogen peroxide and baking soda should i use for teeth whitening?

what amount of hydrogen peroxide should i use with what amount of baking soda in order to make a whitening paste??
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This technique slightly helps whiten teeth, but not nearly as effectively as the gels designed for whitening teeth that contain Carbamine Peroxide and can be purchased at dental offices along with the carrier trays that are needed to hold the gel on the teeth. To use the peroxide-baking soda technique, you should use enough baking soda in a small bowl or disposable that can then be picked up by a toothbrush for several applications to the teeth. Then add enough medical hydrogen peroxide to make a gooey paste, the thickness of toothpaste.
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