Teeth whitening kits which is better?

So i want to buy a teeth whitening kit which is better ivory white or brite teeth. Result wise and how long it lasts.
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Over the Counter, I would recommend Crest Whitening Strips. There is one that is called premium, which will have the highest bleach concentration. The younger you are, the better the OTC whitening strips will work ie: teens. But if you really want the ultimate best bang for your buck, that would be to have bleaching trays made in a dental office. They should run you around $150 each tray (upper & lower) so about $300 total and they should include free bleaching syringes with your trays. Then if you need more bleach in the future for maintenance, the bleaching syringes are only like $30 for several syringes. I would HIGHLY recommend this route. The dental office bleach is so effective that once your teeth are the shade you'd like them to be, you almost never have to bleach for maintenance. I haven't bleached in over 2 years and my teeth still aren't back to their original color. You could also make your own trays with otc things from wal-mart in the dental section and then just buy the bleach @ a dental office. The dental office bleach strength is really what is the source of quality in getting it all done through a dental office. Good luck, email me if you have any further questions.
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