what's a good home teeth whitening kit?

i am very self concious of the colour of my teeth.. can u please tell me which is the best whitening kit ppl in the UK help me !!
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I've always had the same feeling since I was 9 because I have tetracycline stains - which is deep staining of the teeth because of an antibiotic I had to use when I was younger. I always use "Arm and Hammer Enamel Care Sensitive" or one of the "Macleans" whitening ranges. Both are toothpaste and I felt like they really worked even when I used them every other day!! Although they are perfectly fine to use everyday - I just like to use whitening one day then sensitive the other day. Personally I've never used any of the products with the gel and the light as i've heard from my dentist that some of them are just a waste of money and will never work. You could try asking at the dentist for an at home whitening course. These are 100% approved by the Dentists but you can do them in your own home. It basically includes a tray and gel and you keep them on for about 15 / 20 mins a day. But definately ask the dentist as there's just so many companies that are ONLY out to make a profit out of other peoples problems
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