Crest 3D White, Whitening Toothpaste, Radiant Mint, 3.3 Ounce, Pack of 4

How does this toothpaste whiten teeth? Asking as the only active ingredient is fluride, same as normal toothpaste!

Does the tube come with the silver seal on it to show it hasnt been tampered with

I purchase crest 3d white x3, packaging is showing made in canada and not usa. there is no security tab on tube or packaging?

Got my package yesterday. (june 5).. 3 boxes of toothpaste. but the expiry is oct 21.. how am i supposed to finish all 3tubes in 4 months