Teeth whitening?

How successful is DIY teeth-whitening?
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Is that something you buy in stores?....i just recently went to my dentist...and he made a mold of my teeth and i am going back in to get my over night bleach and tray...i have to do it for 2 weeks..im really excited to be using something that i think will finally show results...it cost 300 dollars and he said you do it for 2 weeks...and then you just touch them up once in a while and it lasts a LONG TIME...the results and the bleach...:D i think 300 is reasonable...for how long it lasts...if thats what your talking about you can email me i will let you know how good the results are after a week or so....i know some people who used it and after they woke the first night said they almost FAINTED! haha im so excited...my teeth arent like yellow or nothin just not as white as id like...
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