teeth whitening by dentist - I think few methods are available - which one is the safest?

Hi, by safest I mean no cancer risk as some laser methods as well as components/whitening material used is cancerous. (for example some material have/one reason is free radicals) THANKS.
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After much deliberation and debate the process of teeth whitening has been deemed both safe and effective. In fact the Hydrogen Peroxide or Carbamide Peroxide as bleaching whitener for your teeth whether teeth whitening at home or professional teeth whitening In-office. Teeth whitening not caused any cancer Studies have indicated that Carbamide Peroxide and Hydrogen Peroxide chemicals generated in the whitening process aren't carcinogens in the mouth, has not caused any cancer in gums or mouth tissue. The laser or bleaching lights were designed to a activator acts as a catalyst that speeds up the breakdown of the hydrogen peroxide into its reactive components. It can speed up the whitening process and enhance the whitening results. In fact, the lifht is not really "laser", so it is safe. The teeth whitening laser or bleaching lights are merely a marketing gimmick. It seems the only thing a light can accomplish is dehydration of the teeth, which can make teeth look whiter temporarily (usually a few hours). there are main Zoom! and BriteSmile, u can check my site to know, Compare for professional Zoom! and BriteSmile® teeth whitening In-office What works better? http://www.teethwhiteningbest.com/teeth-…
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