Question: (A little over Half a Page Minimum + 1 Reference)

Background of Question:

The use of 3-D printing has made some impact in the medical field. The advancements in 3-D printing technologies have enabled a proliferation of clinical achievements and helped save lives. 

Question: 

Please share some of the technical or regulatory challenges in using this advancement? (A little over Half a Page Minimum + 1 Reference)