Inexpensive but effective teeth whitening?

what are the best teeth whitening products that wont completely break my wallet?
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(This is going to be a somewhat long, but informative answer). You should definitely go with whitening mouthwashes. You won't notice the difference right away, but you will notice over time, maybe a week, or a few days, as long as you use the mouthwash once in the morning and once at night for 60 seconds (just like a regular mouthwash). I'm sure you've seen the commercials for it, like Listerine White and Crest White. They really do work. The brand I would recommend the most would, surprisingly, be the generic brands (like Equate from Walmart or Kroger from Fred Meyer). I did a science experiment for my chemistry class as to which whitening mouthwash was most effective in teeth whitening. I found that Kroger was most effective out of the bunch, and Listerine White and the Walmart brand did just as good. The ones you should not buy are Scope and Crest White. Although the two do whiten your teeth, they don't do it as quickly or as well as the other three I tested (I also tested the 3% hydrogen peroxide solution you find in stores for less than a buck, because apparently, you can use that as a teeth whitener, too. But DON'T use it. It SUCKS at whitening. It did the worst in my experiment). The bottles generally go for $5. I got a huge bottle of the Walmart brand for $5, and a smaller Listerine bottle for $5. You'll find these mouthwashes in the mouthwash aisle in solid white bottles.
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