IMO teeth are the worst part of the human body. Hard to take care of, will inevitably fail, not replaceable, massively painful for even minor injuries. Evolution really screwed the pooch on teeth.
https://m.youtube.com/watch?v=t4RgBZlKlJI
Evolution expects us to grind away about a millimeter of our teeth while we are young by eating rougher things to make way for wisdom teeth, for example.
For healthy teeth, you should be very hydrated. If your mouth isn’t watering, you might not be hydrated enough.
> One of the areas where human crystal formation happens
Especially one of the areas where you want crystals to form. Unlike in your urinary and bladders. ;)
Feels like engineering: It's all trade-offs.