Teeth Whitening Question?

What is the best whitening system? Is it easier and better just to go to the Dentist and have him do it?
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From my experience the dentist whitening system works much better, especially if you can find a time when they have a good deal on it. They will make imprints of your teeth and create trays especially for you, and then you can always reuse them and you will only have to pay for the chemical for future appointments, it worked so well, and im a smoker and my teeth were still much whiter then they have ever been before. Ive also tried strips from the store and stuff, but they never worked for me.
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