Back in my day, the schools would bring in dental staff to talk to you about your teeth . They brought these with them. They stain the plaque red/pink so you can learn to brush properly.
Even today, our elementary school brought in dental hygienists to work on the kids’ teeth. I don’t think they use the tablets anymore, though. Hell, my wife didn’t even know about these tablets.
Back in my day, the schools would bring in dental staff to talk to you about your teeth . They brought these with them. They stain the plaque red/pink so you can learn to brush properly.
Fixed it for you
At mine they would distribute packets of mouth rinse that were fluoride-heavy. You would feel the taste at the back of your jaw, it was terrible.
Even today, our elementary school brought in dental hygienists to work on the kids’ teeth. I don’t think they use the tablets anymore, though. Hell, my wife didn’t even know about these tablets.
In the time period they were used they were probably made of asbestos and cigarette butts though.