As a side note, turmeric has other beautifying properties as well, and can be taken orally or topically as a mask to shrink the pours on the face, and is used by Indian brides before their wedding day for just this reason.
Anyway, using about a half tablespoon dried organic turmeric powder and a bit of water to make a paste, I gave it a go. You do have to be very careful because anything not inside of your mouth that comes in-contact with it will be dyed bright yellow (including the toothbrush). But, as you might have guessed, it works like a miracle to whiten teeth.
Turmeric would also be great for oral hygiene, not just tooth whitening, because it is such a strong anti-inflammatory, which is good for the gums--since 90% of people over the age of 30 have gum disease, and is also a strong antimicrobial, so it kill all those bag germs causing tooth decay and gum disease (and be sure to take your vitamin K2).
Directions: use 1/2 tablespoon dried organic turmeric root (bulk in any health food store), add just a bit of water to make a thin paste. I use a small--real small--cup for this. Scoop it up with the bristles of your toothbrush (which will become irreversibly stained), and brush like normal. Enjoy!