When did brushing your tongue become a thing? (teeth, baby, flossing)

[MillennialUrbanist]

Brushing your teeth existed in the American society since time immemorial. Flossing came about more recently, but definitely before I was born. So I remember being told to brush and floss ever since I got my baby teeth. It became as much a part of my daily bathroom routine as SS&S, as it should be (well, the "shave" part started when I was about 15).

But I don't remember hearing that I need to brush my tongue until well into my adulthood. I also don't recall toothbrushes having a slightly rough surface on the back of the actual brush. Today, almost all toothbrushes, except the cheap dollar-store ones, have a tongue-brushing surface on the back.

When did this come about? Can anyone pinpoint a specific year tongue-brushing went mainstream?

[oldgardener]

I've been brushing my tongue since at least the 70s. No special brush for it, just use my toothbrush.

[in_newengland]

I think I first read about it back in the 1970s in a Yoga book. I've never done it though. Brushing teeth was done back in caveman days using twigs to clean their teeth.