teeth whitening....??

i want my teeth whitened at the dentist but how old do u have to be and how much does it cost ?? I live in the uk btw
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i worked at a dentist office for 12yrs and know that it is around 200.00 for one session of the zoom whitening technique. the problem is that your teeth become extremly sensitive for several days and once you do whiten it becomes easier for the teeth to stain afterwards because it takes some of the protective enamel off the tooth surface which exposes the softer and more porous dentin underneath which is more prone to staining. with that being said whitening your teeth is wonderful but takes dedication to keep up the beautiful results. you may want to try crest white strips. they work well but takes longer because the ingredients aren't as strong and it is less expensive. Good luck to ya.
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