What other teeth whitening product works as well or better than crest White strips?

I used crest whitestrips and had fabulous results, my teeth looked great! Then after nine months they start to fade. Now I'm ready to either get crest white strips again, or if there is another product that whitens teeth better I would love to know :] thanks
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Crest white strips are by far the best over the counter whitener. Teeth stain very easily and if you drink alot of pop, coffee, or tea it happens faster. We usually tell people that whitening is not permanent and that they will have to repeat in 6 months to a year.
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