Teeth Bleaching/ Whitening gel painful! Is this normal?

I purchased some Plus white teeth whitening gel at my local drug store because although my teeth are white I wanted them to be sparkling and perfect... So then I put it on...And the first 3 days were fine... but today it was burning my gums and when I took a breathe in a sharp sensitivity that was strong gave me a sensitive pain in my tooth! And finally my gums were bleached but the came back to normal.... Is this normal? I think it made some of my teeth more sensitive... and My gums are a little sore still... Here are the ingredients of the product- WATER,POLOXAMER 407,GLYCERIN,HYDROGEN PEROXIDE,METHYL SALICATE,SODIUM SACCARIN,PHOSPHORIC ACID.
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Some OTC whitening agents can be very dangerous if used improperly or too long. Many are too strong for an OTC product (in my opinion!) Hydrogen Peroxide will burn tissue. Try putting a drop of hydrogen peroxide on your finger...it will turn white. That's a chemical BURN! This is what is making your gums sore, you have burned them chemically. Phosphoric Acid is what we dentists use to DISSOLVE tooth enamel. Yes, it will eat away at your enamel! This is what is making your teeth sensitive. You have opened tiny holes in the exposed root surface (called dentin tubules) They communicate with the nerve and that it why your teeth are sensitive. Stop using the product immediately. Rinse with warm salt water for a few days and brush very gently. You can also use Sensodyne toothpaste to "close" the tiny holes and diminish the sensitivity. This why we as dentists try to encourage people not to whiten on their own. Some of these products can be damaging. The ones that are safe, like Crest WhiteStrips are such a low concentration that they take a long time to work. In 20 years of practicing dentistry, I have found the most effective and safest products are the whitening gels (10-15% carbamide peroxide, a safer form of hydrogen peroxide) placed in a custom-made tray (made by your dentist) which allows you to keep the gel off your gums so that they do not burn. These gels also DO NOT contain phosphoric acid! I find this concentration gel works the best for most people and causes the least sensitivity. And, once you pay to have the trays made by your dentist (usually around $200) then the gel is cheap. The trays can last a lifetime if you take good care of them. so, the cost ends up being less than most of these OTC products. If the pain lasts more than a couple of days, see your dentist. Good luck, Dr. Paul
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