Hello, George and thank you for your question.
My apologies that you did not receive an earlier answer, but different experts are online at various times, and I recently signed online and was notified of your question. Your patience is greatly appreciated!
Teeth whitening kits vary by manufacturer and so does teeth whitening powder. Some may contain contents that can cause damage to your teeth and gums, so you need to know which have no or the least adverse side effects.
Crest Pro Strips and another brand, Touch Of White Smile Whitening and Bleaching Kits, listed in the site below, are considered the best over the counter kits; you will read the reasons why, in the article.
As you can see, activated charcoal powder is another method to whiten teeth. Details about this are in the website above, also.
Everyone's mouth is different and sometimes, the kits with the gel made of 36% carbamide peroxide can be irritating to the teeth and gums and cause pain and sensitivity. If this happens, it is recommended to discontinue use of the product and/or use it less often.
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