Teeth whitening, have you done it?

Has anyone paid professionally to get this done? Did you see a remarkable difference? Was it worth the money? How many shades whiter do you think you got your teeth and last but not least did it make your teeth sensitive and for how long? I am looking into doing this but wanted to ask some questions first. Thanks Jenn
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NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO I had "Zoom" whitening and it ruined my gums..they were black for 3 weeks and now some of my gum tissue is missing! It was a huge difference the first day, but after a few days they seemed to look like they did before the procedure, but they are actually whiter...but at a cost of $500 and future gum surgery...and it HURTS LIKE HELL. Please do your research before you do this, it is generally safe, but anything with gel and a light.....stay away!
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