Effectiveness:
“In regard to comparative effectiveness, Gerlach [2003] (use our ‘clinical studies’ link above) found that teeth whitening strips make a more effective choice than other at-home approaches such as whitening toothpaste or paint-on whiteners.
And although research performed by Bizhang [2009] did not find whitening strips to be as effective as a 10% carbamide peroxide tray-based system, many other studies have (Ferrari [2007], Gerlach [2000][2003], Karpinia [2002]). This suggests that most people who use whitening strips should expect to see at least some results. And for a very large percentage of these people, it may very well be a very satisfactory one.”
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Dangers:
“While it is true that teeth whitening by bleaching does work, it does not come without side effects. There are many reported incidents of increased tooth sensitivity after bleaching. Prolonged exposure to bleaching agents can damage tooth enamel. If the treatment is not administered properly, there can be complications like gum irritation. The oxidizing agents are very strong and can damage the soft tissues of your mouth. The bleaching effect can also cause irritation and increased sensitivity to cold and hot fluids and sometimes even to air. In the case of home bleaching, there is a chance that patients might ingest some of the bleaching gel. In such a case, the person might experience burning or nausea.”
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How long do the effects last?
“On average you can expect to have whiter teeth for 6 to 9 months after teeth whitening, but this will vary from person to person. ”
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