I am endevouring to convert CT scan of patient's bone into a print. I have used 3Dslicer to go from Dicom to .stl but I still have part of the supporting plate included in the model

I tried to use mesher to remove the part that I do not want but it will not select a part and then freezes (using w7 64 bit 16Gb Ram)

Here is a screenshot of what I have viewed in Mesher (please click to enlarge)


Thanks