so, after months of persistent hydroxyapatite treatment, that one split tooth does seem to finally be reconnecting to itself, although all that shit that the dentist put in there seems to be getting in the way. and, unfortunately, it might recombine right over the coffee stain. we'll have to see if that works itself out, eventually.

and, the one that seemed like it was clearing up is not almost entirely free of stain and apparently rebuilding.

my tentative conclusion is that this does seem to work, but it's overwhelmingly slow and requires great patience.

again: the tactic is to find  source of hydroxyapatite (i'm using crushed cow bones) and use it as a daily topical. i've posted numerous peer reviewed articles that your body will absorb it intact, but it was kind of a hail mary to hope it would actually rebuild a periodontal pocket, which is what i have from some fairly bad recession that was probably worst about 10 years ago and that i'm trying to avoid merely painting back over.

i'm holding off on the gums until i figure out the iron issue, and the bone issue is probably related as a root cause.