Do Crest whitening strips really work?

to whiten teeth up? how much are they ususally cost?
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Yes, they work very well. I'm using them right now and I noticed a difference after only 2 days. They cost between $30 and $40 for the 14-day regular pack. For the premium and premium plus, they get a little more pricey. Those go in increments of 7-days and 3-days. A word of warning: they make my teeth very very sensitive. It depends on the person, but you might have to use them once a day instead of twice a day, in which case the 14-day pack will actually take you 28 days. Also, stupid moment. A couple nights ago I fell asleep by accident, watching TV while I wore them. I woke up at 2:30 in the morning with the worst tooth pains of my life, and could hardly eat anything at all the next day, regardless of whether it was hot or cold or not. Take care to not leave them on for more than half an hour at a time. If you're careful though, and prepared for them to not work in exactly the time expected, they work amazingly. My teeth are very white and I'm not even finished my pack. The whitening effect lasts about a year, maybe longer if you're careful not to eat foods that stain, such as wine, spaghetti sauce, smoking cigarettes etc.
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