You are correct in that it is difficult with normal size specimens to over
decalcify using buffered EDTA solutions.

If tissues are left for extensive periods of time the tissue can shown signs of
maceration. We had this problem when decalcifying large pieces of dog jaw in
EDTA (buffered pH 7.35). We assumed that this was a result of bonds formed
during fixation being broken.
After this problem we kept a close eye on decalcifying specimens and if there
appeared to be any change in the soft tissue appearance we placed the tissue in
our formalin fixative again for 24 hours before continuing with the
demineralization.
Barry

Bro Lauren Ball wrote:

> Carmen,
>     I didn't think it was possible to over decal in EDTA.  RDO yes, any of
> the acid yes.  I've used EDTA and EDTA tetrasodium salt, and mixtures of
> these.  I find EDTA to slow for routine work.  Bone marrows can take up to
> 24 hours.  But they look great.  RDO only takes 15 minutes.
> Lauren
> ----- Original Message -----
> From: Buttigieg Carmen at MOH <carmen.a.buttigieg@magnet.mt>
> To: <histonet@pathology.swmed.edu>
> Sent: Monday, May 29, 2000 6:00 AM
> Subject: Bone Marrow Trephines
>
> > Dear Histonetters
> >
> > I need your help!
> >
> > We routinely receive bone marrow trephines which are quite boney. We
> usually
> > decalcify in EDTA but sometimes the endpoint is overshot and the cellular
> > structures are ruined. We do not have a resin set-up, we process
> everything to
> > paraffin. We do not have an x-ray set-up either.
> > Is there any way to cut a paraffin embedded bone marrow trephine on a
> manual
> > rotary microtome without having to decalcify it?
> >
> > Thanks.
> >
> > Carmen
> > St. Luke's Hospital
> > Malta
> >
> >