I’ve been thinking about this recently - fluorapatite is stronger than hydroxyapatite when it bonds to enamel, and less soluble by acid. But fluoride doesn’t occur in any natural processes in the body - while hydroxyapatite is a perfect biomimetic - very safe, you can swallow it safely - and also works great in toothpaste to remineralise teeth.
Currently using BioMin F (fluorapatite - very little fluoride due to a novel delivery mechanism but still) but considering switching to BioMin C (nanohydroxyapatite)
I've used both apagard and boka toothpastes with nanohydroxyapatite and I've enjoyed them, though my tooth sensitivity is not totally cured. I still get a jolt of pain from sweet things on certain teeth occasionally.
These n-Ha toothpastes seem at least equal to if not greater than high-fluoride options (in effectiveness) I tried previously like sensodyne and prevident (prescription-strength). I would say the boka mint toothpaste tastes better also, and as a bonus their electric toothbrush is much nicer than the old one I'd used a few years ago.
I still drink water with fluoride in it as well, mostly because it's the best tasting water I've come across. (From a city I grew up in, and I still fill jugs full to drink at home) I have well water at my house, which is safe as far as I know, but I still feel hesitant to swallow it.
Another option is just hydroxyapatite without the nano (sometimes nano particles end up having their own safety issues). A higher hydroxyapatite concentration might work almost as well. Kinder Karex is such a toothpaste. https://www.consumerlab.com/answers/finding-the-best-toothpa...
Currently using BioMin F (fluorapatite - very little fluoride due to a novel delivery mechanism but still) but considering switching to BioMin C (nanohydroxyapatite)