Hahaha dude, back in 2014 i asked a dentist about the reasoning behind hit, he basically said something to the effect of "if you painted a fence and you wanna plug some holes, throw a fist full of sand at it to plug them. Not mentioning the" sand" falling to the ground. They sell banana flavoured flouride for kids, ive talked to kids that tell me they just swallow that shit.. Literal nerve poison.. https://www.thelancet.com/journals/laneur/article/PIIS1474-4422(14)70119-X/fulltext