Wong JY, Pfahnl AC. 3D printing of surgical instruments for long-duration space missions. Aviat Space Environ Med 2014; 85:758–63.
Introduction:
The first off-Earth fused deposition modeling (FDM) 3D printer will explore thermoplastic manufacturing
capabilities in microgravity. This study evaluated the feasibility of FDM 3D printing 10 acrylonitrile butadiene styrene (ABS) thermoplastic surgical instruments on Earth.
Methods:
Three-point bending tests compared stiffness and yield strength between FDM 3D printed and conventionally
manufactured ABS thermoplastic. To evaluate the relative speed of using four printed instruments compared to conventional instruments, 13 surgeons completed simulated prepping, draping, incising, and suturing tasks. Each surgeon ranked the performance of six printed instruments using a 5-point
Likert scale.
Results:
At a thickness of 5.75 mm or more, the FDM printing process had a less than 10% detrimental effect on the tested yield strength and stiffness of horizontally printed ABS thermoplastic relative to conventional ABS thermoplastic. Significant weakness was
observed when a bending load was applied transversely to a 3D printed layer. All timed tasks were successfully performed using a printed sponge stick, towel clamp, scalpel handle, and toothed forceps. There was no substantial difference in time to completion of simulated surgical tasks with
control vs. 3D printed instruments. Of the surgeons, 100%, 92%, 85%, 77%, 77%, and 69% agreed that the printed smooth and tissue forceps, curved and straight hemostats, tissue and right angle clamps, respectively, would perform adequately.
Discussion:
It is feasible to 3D print
ABS thermoplastic surgical instruments on Earth. Load-bearing structures were designed to be thicker, when possible. Printing orientations were selected so that the printing layering direction of critical structures would not be transverse to bending loads.