I missed the original thread on Bone IHC, so now I would like to add my two
cents worth.

I too have gone to fixing with Zinc formal which requires much less antigen
retrieval, but when I do require pretreatment to access the antigen site, I
use enzyme digestions rather than hier.  We have found that we can control
the process much better with enzyme digestion and it causes less damage and
dislodging of the sections.  I also use silane coated slides (plus slides).
There are certain components in bony tissues that require enzyme digestion
anyway and you must completely decalcify or the hydroxy appetite will block
access to the antigen site, or take on everything because it is so porous
and absorbent.  Before IHC I always treat the deparaffinzed slides with 0.4
M EDTA to assure complete decalcification.  There are so many idiocyncrities
about bone IHC, it is a whole different science from soft tissue IHC.
Patsy Ruegg