In the early 1900s, only 5% of Americans brushed their teeth daily. 5 years later it was 80%.

What changed?

Claude Hopkins ad campaign.

Hopkins made a trigger so people could feel if their teeth were dirty. By running your tongue across your teeth, you could feel grime. After brushing it wasn't there.

He also helped make the minty taste popular.

This minty feel of toothpaste, its a bit uncomfortable. People knew that.

Hopkins positioned it as that's how you know its working! You can feel it cleaning you! And the mint aftertaste is proof.

There was already an army of door-to-door salesmen failing to sell toothpaste.

But all it took was a positioning change for Hopkins to make his brand, Pepsodent (now Unilever) one of the biggest brands in the world (and help Americans dental hygiene!)