I don’t have a subscription to the NYT but receive their newsletters, and one this morning asks the question - is it better to brush teeth before breakfast or after?
Would you change your ways? I think I might - am losing enamel rather rapidly!
Another website explains…
I read about this recently and the only thing I was missing was to not rinse away all the toothpaste after brushing because the fluoride should stay on teeth as long as possible. Seems sensible.
So, now I turn in at night with minty breath freshness. (And, possibly a cat’s moustache.) 
I shall brush my teeth as soon as I get up, go to bed unrinsed, and hope that this will soon become a habit.
Changing habits - not easy to do!
After brushing my teeth last night, I went into my bedroom, which I’m currently sharing with my cat for a few days until he has recovered from an operation, and after feeding him I was about to retire when I realized that I had rinsed! No frothy cat moustache! So back to the toothbrush for a second brushing!
Ah ha! The feline reminder 
For a moment there I thought you had cracked the problem of how to clean a cat’s teeth.
Fluoride applied on the surface of the teeth (as compared to being taken internally) may strengthen them. But I can’t get over reading that toothpaste was originally fluoridated after approaches from the aluminium smelting? industry as a way of disposing of their (toxic) byproduct.
Fake news alert!
Quora help -
- Answer to Is fluoride a byproduct of aluminum production? by Half Mckenty
“Fluoride is a chemical compound that contains fluorine and oxygen. It is not a byproduct of aluminum production.”
- Answer to Why do they keep using fluoride in toothpaste when studies claim it can make aluminum go to the brain and is linked to Alzheimer’s? by Alan Young
“Fluoride is an element. Aluminum is another element. Elements don’t change one into the other except in nuclear reactions.”
Clear info:
- Answer to Is fluoride good for humans?
The elephant in the room is sugar consumption, the cause of tooth decay but hey dont stop that sell them something else that way they can keep their teeth and die from diabetes and heart disease.
everything in moderation… 
Including moderation. 
We’ve all got to die sometime - I hope it’s quick for me.
Except sugar.