By Peter Zelinski
F E AT U R E
Reimagining
Implants
A medical-industry contract manufacturer that built its
reputation on CNC machining is now helping its customers
realize the advantages of additive manufacturing.
onald Dunn, vice president of medicalindustry contract manufacturer DiSanto
Technology, says the photo on this page
illustrates the future of spinal cage implants.
The part shown is actually a scaled-up model
DiSanto uses to illustrate this design to medical
device companies. Surgeons and other medicalindustry professionals who are knowledgeable
about spinal surgery look at this model and immediately appreciate the beneft: bone ingrowth.
A spinal cage implant essentially serves as
a spacer between adjacent vertebrae that are
fused together during spinal surgery. The part is
usually machined, whether from a plastic (PEEK)
R
4— AM Supplement
or from a titanium alloy. Because it is machined,
the part is typically dense and solid.
This new design is self-evidently better, Dunn
says. Because the part's mesh allows the patient's bone to grow into it, the body accepts this
implant such that the ft improves over time. Few
would contest the value of this ingrowth, he says.
It's just that machining has never offered a way
to create this mesh geometry. The mesh seen
here was possible because this part, instead of
being machined, was produced through additive
manufacturing. The part was grown in successive layers on an electron beam melting (EBM)
machine from Arcam.