Why does OTC teeth whitening products make my teeth sensitive?

How do these products work and why oh why does it make my teeth so sensitive?
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It's the solution that is making your teeth hypersensitive and probably irritating the tissue as well. Use warm salt water rinses for the tissue truama. This solution of carbamide peroxide can dehydrate the teeth and opens the tubules for the whitening process. You need to either "reduce the time" each day you wear them, cut back time and "skip a day" in between bleaching, or "stop" using them altogether and "see your dentist for professional bleaching" trays or the one hour process. While the teeth are sensitive, avoid dark drinks and food and hot or cold drinks or foods until the teeth return to normal. The darker drinks and foods can just re-stain the teeth while the tubules are open during the times your sensitive. Brush with a fluoride tooth paste or use a fluoride rinse to help close the tubules. Excessive stimulation can cause permanent damage to the nerve of the tooth. Use caution with any OTC product, especially where your teeth are concerned. Hope I've been of some help and good luck with your bleaching process. Additional information: If you've used this product before and never experienced this, it could be that the last one was closer to the expiration date and not quite as effective and perhaps this one is stronger or newer on the shelf.
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