Teeth whitening?

I'm thinking about getting my teeth whitened. I heard about laser whitening. Has anybody had it done and does it work? It's going to cost £100 for 4 sessions, or I could get it done at the dentist where they just make one of those gum shield things to put on your teeth with bleach. That will cost £300. Which one should I go for?
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My dentist told me that there are 2 types of teeth. There are teeth that have more of a yellow shade and some that have more of a grey shade. He told me that those people with more of a yellow shade have much better results with teeth whitening, so if you do not fit in this category, I would suggest spending less money on it, as your results wont be as good. However, if you do want to get it done the best, i woudl definitely say spend the 300 and do it at your dentist, then after its done... once a month use something like "crest white strips"... My dentist told me that using the white strips once a month will keep your teeth as white as they became when you bleached or whitened them at the dentist. There ya go, hope i helped
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