Nicely riffed, Rebekah.
Would you believe, F and I are the only two people in the US who have never seen Seinfeld! Now that I know about this attraction to oral hygiene I’m bummed. (A little.)
The whole white sparkle tooth mystique leaves me baffled, but F is caught up in it too. Ultimately wouldn’t spring for the dentist’s professional advances, but did try one course of the kind you buy in CVS. He’d examine the teeth every day, watching for whiteness. 
(See ‘em sparkle, right here on the page?)