Is this a commercial product that has been approved by a regulator to make these claims? Amazing. Newsworthy.

Is this a press release from a university research group, as it appears to be (the site is down)? Then it's nearly meaningless.

You can buy the supplies and make nano silver flouride now, relatively cheaply compared to dental work. If you have a non corporate dentist, you could even ask them to apply it. The basic mechanism has been used on teeth forever, and adding the nano particles prevents the chemical from permanently staining your teeth black or blue (which is why it hasnt ever been more popular to begin with.)

https://fourthievesvinegar.org/tooth-seal/

https://www.newscientist.com/article/2502731-cavities-could-...

I found other sites indicating it's entering trials soon to be on the market next year. That's still a bit speculative obviously, but it sounds more promising that just being a working theory.