I'd be suspicious of those claims – anecdotal but, unless US doctors differ greatly, neither of those are secrets that have been withheld from me by dentists in 3 European countries.

In fact the second statement is surely the basis for most modern dentistry...?

(I said US there because it's an assumption that the US approach to dentistry may be different to rest of the world. From afar, seems more cosmetic focused with a lot more emphasis put on whitening/straightening/veneer/fixing procedures than over here)