What type of file is it. If its a mesh file you should be able to select the vertices that make up the forms and then create a new mesh file from them, I think its going to depend how separate the different areas are. I think this would be hard and time consuming. How was the scan produced and what software is it using. is it not possible to extract 3D models based on density, using thresholds to generate the new 3d images, and then to print each out separately?