Most likely, it removed an infection that was hijacking explorer.exe, then the infection was removed taking explorer down with it
As long as some policies aren't changed as well this should work...
From the blank desktop, hold down the windows key on your keyboard and press R
type in explorer - this should at the very least give you access to files and folders, or hopefully restore the desktop
**if your keyboard doesn't have a windows key, this can be done by hitting ctrl+alt+delete -> applications tab -> new task -> type explorer and hit enter