Kim,
            not much call for this tissue in a dental school, however we have
mounted a lot of very thick sections and whole mounts of various tissues.
First you may want to go from Carnoy's to chloroform or acetone to complete
defatting if that is necessary
For keeping tissue flat there are several techniques.
The one I prefer is to use small solid brass cylinders. These can be made of
various weights and if placed over the center of the coverslip will help keep
the tissue flattened while the mounting medium is drying. The problem with
tissue that is uneven (and I suspect that these may be)  is that the coverslip
often will be raised on one side or one edge. TThis can be minimized by placing
small pieces of thick coverslips around the edges of the coverslip. Also use a
coverslip that is larger than you would normally select and be generous with
the mountant.
If you would like a few of the brass cylinders to try email me you address.
Another technique is to use welled slides and these may be best for this
tissue.
For thicker whole mounts, glass rings are available which can be used top
provide a small raised area for the mountant.
Barry

"Kowsz, Kim P" wrote:

> I am trying to do whole mammary mounts on mice.  The tissue is fixed on the
> slide in Carnoy's for 2-4 hours before being stained in carmine alum.  My
> sections come out very thick even though the tissue is "squashed" between
> two glass slides before fixation.  Is there a de-fatting step that some
> people use to thin the section?  Is there a more specific technique to
> spread the mammary tissue on the glass slide?  Thanks for any help.
>
> Kim_P_Kowsz@groton.pfizer.com