Does teeth whitening infomercials advertised on the internet really work?

I am particularly interested in this product especially when average claim that by combining two products they saw a difference in just two or more days. Does it really work? Please write your honest opinions and thank you.
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You may think about digging for information from researching magazines that are specifically done for professional dentists that feature results of clinical tests of several tooth whitening products. Many of these reports and research materials, however, are sponsored by the manufacturers of such products, so not much can be said about their credibility. The best way to make a dramatic difference in the whiteness of your smile is to either consult your dentist or find a dentist that specializes in cosmetic procedures – and not focus merely on choosing the best whitening system.
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