In SF, I saw these mall kiosks where people were sitting there with these probes in their mouths which bathed their teeth in an eerie blue light. I wish I had taken some pics. It was weird and I am sure it was a teeth whitening thing but I have not bothered to look it up.

It seems, today, unnaturally white teeth are becoming a "must" if one wants to be considered attractive, at all.

(I have a mixture of enamel and crowns, visible, so whitening would involve getting the crowns replaced. . .too much trouble.)

Yeah, I think I decided I'm getting off the white-teeth train when, as I was getting my last crown, the dentist asked me if I wanted to match the color of my teeth or match the color of some kind of Platonic ideal of hypothetical tooth whiteness. If I ever have to get another crown, I'm thinking stainless steel.

Enamel does NOT regenerate. Sensitivity will decrease over a few days if you stop using a whitener, but it's not your enamel regenerating. I wish to god it did.

I have a box of unused whitestrips that I just unpacked from my move. Maybe this will motivate me to actually use them! (And go to the dentist, yuck)