Fortunately, there are some powerful open-source solutions. The biggest issues were related to the fact that the conversion of STL file to CAD model leaves a lot of unnecessary surfaces We discussed this topic recently here: Ī lot depends on the software used to obtain 3D model (STL) from DICOM data. I used to do such DICOM (or 3D scan) -> CAD model conversion in the past, before I knew FreeCAD and had to use the Mesh Enabler plug-in in Inventor which appeared to be the only solution available for students. This topic is quite complex and difficult to realize properly, especially without very advanced commercial software.