Open File Dialog

Is there a way to change the default (alphabetical) listing of files
in the Open File Dialog? I have a directory of Word files that has
several sub-folders. I'd like the folders to be grouped together at
the top of the list, then all the Word docs. sorted alphabetically
from there. The way it is now, all the folders appear in the list,
but separated by a bunch of files. In the OSX finder, I can sort by
"Kind", but that option doesn't seem to be available in the Open File
dialog.

Thanks in advance for your help.