Teeth whitening that is effective yet convenient is a Holy Grail that I might be getting closer to. Bright Smile's Teeth Whitening Pen ($22.50) requires a twist to release the product and then all it takes is a targeted rub with the tip and you are good to go. I tried it for about 10 days on a small stain on one tooth and it did the trick. No mess, no swallowed bleach, no drooling and, best of all, no stain.

There's no secret sauce in Brite Smile; the active is peroxide just as it is in just about every other teeth whitening product. Somehow though, the 8% concentration and the consistency of the gel works.

Although the EWG doesn't like PEG-60 hydrogenated castor oil, published studies demonstrated that it is not toxic at a concentration of 100%. I still feel guilty knowing that the people who harvest the castor oil plant in the first place are exposed to the seeds, which contain ricin, a compound that is only slightly less toxic than plutonium – a single molecule can disrupt a human cell.

On the whole, I think it performs better than Go Smile, another on-the-go whitener, and doesn't require endless rubbing. Bear in mind that Brite Smile is better at micro-targeting specific stains than overall whitening.

By the way, Watts has redesigned its trays to fit better without boiling. I'll be giving them a try in a few days.

Ingredients

Water, hydrogen peroxide (8%), carbomer, glycerin, PEG-60 hydrogenated castor oil, flavor, sodium saccharin, editronic acid, potassium stannate.