Is take home light treatment for whitening teeth safe (from over the counter)?

I'm gong to buy teeth whitener soon from Wal-Mart probably and I wanted to know if the light treatment was safe? If not, what brand do you recommend?
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its mores of a gimmick. the light activated whithener used at a dental office uses a different light frequency than what is sold at walmart. I dont think walmart would sell the light used by dentist to the public as it is a regulated device. The gel may have some interaction with the light but it whitning property is more of a chemical reaction than it is a light reaction, so it is more of a gimmick and will probably not produce much if any difference than traditional gel and tray. Save your money and stick with gel and tray.
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