Black dentifrice, white teeth?

Scientific evidence for the actual whitening effect, however, is still limited. A search in PubMed shows one randomized controlled double blinded in vitro study in which the'Black is White Curaprox® dentifrice is less effective in reducing extrinsic staining than other whitening dentifrices. One systematic literature review and one review article concluded there is insufficient scientific evidence to substantiate the cosmetic benefits of charcoal-based dentifrices.