Do teeth whitening systems really work?

The ones where they make trays specific to your mouth and then you put a gel on the trays and leave on overnight for 7 to 10 days
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In the 70's and 80's there was teeth whitening gels on the market. They were taken off the market because they ruined peoples teeth. I have seen people with super white teeth and they are transparent all along the edges, which means the enamel is gone and rotted teeth are soon to follow. if you want white teeth, brush you teeth with sugar or salt or peroxide and baking soda will make your teeth much whiter seriously, crushed strawberries used as toothepaste will whiten your teeth. Steer clear of the whitening stuff no one has white teeth - they have a red tint or a yellow tint, naturally Stains make your teeth dull, clean them with natural abrasion
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