How many shades lighter can an overnight bleaching gel do for one set of teeth?

for teeth whitening
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Overnight bleaching of teeth is not very effective. It take several week for OTC whiteners to work. This is due in part because of the lower amount of chemical used for comsumer saftey. You can go to a dentist and have a one day treatment done that would have better results then 3 weeks of overnight whiteners but you are going to pay a bit more too. So if your trying to get them white fast see a good dentist with a whitening process that uses utlraviolet light, that is the fastest results you can get.
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