Do teeth whitening strips weaken teeth?

If so, how long do they stay weakened... or is it permenant?
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The teeth whitening gel penetrates the enamel to the dentin beneath in order to oxidize stain pigments that are trapped in micro-crevices on the surface. teeth are made of enamel rods (tubes). You are whitening what is inside of them and not weakening the entire structure. the most common complaint of whitening agents is that teeth are sensitive. That's because these tubes are now open. Desensitizers like flouride are tubule blockers. cavities weaken enamel. They destroy the infrastructure. No, bleaching is not permanent. Coffee, tea, and other foods and liquids will restain the teeth. Most people will need a touch up within a year after bleaching depending on their diet. And yes, do not get that gel on your gums. after applying the whitening agent, take a tissue or Q-tip and wipe the excess off your gums. I bleach my teeth every 5 years but stay away from colas, limit my coffee to one a day or substitute it for one cup of tea a day. --dentist
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