Tanda Pearl- reviewed and rejected
The Tanda Pearl tray has an on/off switch and inside the molded plastic there is a thin metal band. Switched on, and loaded with “ionic” gel, hydrogen peroxide in it gel “turns into oxygen, which penetrates the tooth enamel, attacking dark-colored molecules, to break down stains set deep inside the teeth”, according to Tanda.
This “turns into oxygen” part has me raising my eyebrows. According to Wikipedia, hydrogen peroxide is an “oxygen-oxygen single bond” and all living creatures turn hydrogen peroxide into oxygen. The chemical formula for hydrogen peroxide is H2O2 - it contains one more atom of oxygen that does water (H20). So, I don’t really believe that Tanda’s plastic tray, ionic or otherwise, is doing anything miraculous by transforming H202 into oxygen.
Although the gel is very thick, I found that after about three minutes it started to seep from the tray into my mouth and I had to concentrate very hard in order not to swallow it. I find this to be the case with most trays and dislike using them for this reason. It probably isn’t a great idea to swallow Tanda’s gel on account of the sodium hydroxide, known as lye or caustic soda and a strong irritant and corrosive.
One thing I will say, is that Tanda Pearl’s gel did not make my teeth or gums feel at all sensitive. This is probably due to the inclusion of potassium nitrate, an active ingredient for desensitizing teeth.
Since I wasn’t terribly impressed by Tanda Pearl’s results, I marked the end of my trial by buying Crest’s whitening strips. At $58, they cost the same as a refill set of Tanda’s gels, don’t require the nearly $200 upfront investment in the Tanda device, don’t threaten to drip down my throat and do a better job of whitening.
Ingredients in gel: Water, Sodium Hydroxide, Carbomer, Edetate Disodium Dehydrate, Potassium Nitrate, Hydrogen Peroxide, Glycerin, Sodium Saccharin, Natural Peppermint Oil.