removed from those surfaces in order to have adequate
cleaning function. Validation of both cleaning and sterilization requires access to these surfaces to verify that
the cleaning or sterilization process has occurred.
The order of manufacturing can be different for
additive manufacturing than for traditional. Consider
a bone replacement device that contains an external
porous region to enable biological attachment (
osse-ointegration) to living bone. A traditional technique
might begin with machining, followed by cleaning to
remove machining fluids, followed by coating with a
porous layer. In contrast, with 3D printing, the porous
layer might be fabricated as part of the initial build.
Any post-printing machining and cleaning would be
complicated by the presence of the porous layer.
On primary strength of additive manufacturing,
especially for medical devices, is that the technology
enables an economically feasible approach to “
one-offs.” Patient-specific devices raise the variations in
dimensions and shapes. This in turn raises the issue
of cleanability and of cleaning validation. Still more
contamination and cleaning issues can occur due to
one of the primary strengths of the additive approach,
the ability to economically fabricate patient specific
devices. Variations in dimensions and shapes can
complicate both cleaning and cleaning validation.
Back to ASTM
Industry standards and guides will continue to be
developed or adapted in response to new technologies
like additive manufacturing. In May, the ASTM F04
Committee on Medical and Surgical Materials and
Devices held a workshop on Additive Manufacturing
for Medical Applications4 in order to explore the need
for new or revised ASTM standards. FDA CDRH
personnel helped to plan and conduct the workshop.
In our own view, additive manufacturing may not
require an entirely new set of industry standards but
rather a mindfulness of which standards might need
to be modified to meet new challenges.
1. Kanegsberg, B. “‘Perfect’ Cleaning Process? New
Guidance,” Clean Source, August 2016.
2. FDA draft document, “Technical Considerations for
Additive Manufactured Devices; Draft Guidance for
Industry and Food and Drug Administration Staff.”
3. Kanegsberg, B., E. Kanegsberg. “FDA Additive
Manufacturing Workshop,” Controlled Environments,
January/February 2015. http://www.cemag.us/arti-
Barbara Kanegsberg and Ed Kanegsberg (the Cleaning
Lady and the Rocket Scientist) are experienced consultants
and educators in critical and precision cleaning, surface
preparation, and contamination control. Their diverse projects include medical device manufacturing, microelectronics, optics, and aerospace. email@example.com