What is a good teeth whitening product?

What really works? Crest white strips? What works? Anyone have a good answer or do you think all these products are a waste of money? I smoke too btw, but thats not the question, what are good products?
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Fortunately, there are many ways to alleviate the damage done to your teeth. Well, I will briefly describe some of the more effective teeth whitening methods available today. While whitening trays are an effective teeth whitening method and often yield satisfactory results, The tray is placed in your mouth and worn for about 60 minutes each day for a couple of weeks. But the process is just too long for some people. A significant advancement in teeth whitening occurred with the use of laser technology, which makes it possible to achieve in a one hour visit to your dentist results that used to take weeks to see at home. One of the best teeth whitening methods available today, laser teeth whitening involves placing whitening gel on your teeth and then activating it with light from a laser. This activation greatly increases both the speed and effectiveness of the whitening process, resulting in your teeth being whitened by as many as ten shades. On the downside, though, while laser whitening is one of the most effective teeth whitening methods available today, it is also the most expensive option as well, and can cost as much as $1000 per treatment in some cases. For those who are unwilling, or unable, to spend that kind of money to have their teeth whitened, a more economical - though less effective - whitening method is the use of teeth whitening strips. Whitening strips contain a peroxide based whitening agent similar to that used in other teeth whitening methods and are placed on your teeth for approximately one hour each day for about two weeks. While whitening strips are able to considerably whiten your teeth, the major drawback is that they only come in contact with the front of the teeth. This makes the gaps or spaces between your teeth even more noticeable as the front of your teeth are whitened. For some this may not be a problem, but for others it may rule out the use of whitening strips altogether. I've made the most comprehensive research to find the best teeth whitening products, and you can find it here: http://tinyurl.com/mc72j5
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