F E AT U R E
By Peter Zelinski
Medical
Parts on these pages illustrate how additive manufacturing helps improve
the design of medical components. The metal parts in these images
were all produced by Innovative Medical Device Solutions (IMDS) via direct
metal laser sintering. Learn more about IMDS on page 2.
Digital Porosity
Implants such as these acetubular cups have a porous surface layer for "osseointegration," or for the
patient's bone to grip by growing into it. In the past, adding this porous layer has involved a special step such
as plasma spray. But an additive process allows the intricate layer to be made with the rest of the part, bringing advantages that go beyond just simplifying production. For example, the additive part can be designed to
transition to the porous layer gradually, improving the integration with bone. In addition, the part's structural
strength can be augmented with features that plasma spray would have precluded, such as the ribs seen
in the implant on the right. Michael Siemer, additive manufacturing engineering manager with IMDS, says
software from companies such as Netfabb or Within Technologies can be used to digitally design this complex
organic geometry. Software such as this generates complex forms from user-defned boundary conditions.
4— AM Supplement