3D printing the past and future

skullSome 90 years ago, the fossilized skull of an early hominid was found in Africa. Two things made this fossil unique: The first was that it was the skull of a young child, perhaps 3 years old. The second was that the fossil's shape of the brain had been preserved as a naturally occurring cast on the inside of the skull. These features gave a strong implication that the brain of this early hominid continued to grow well after birth, a feature that is much, much more pronounced in humans than in any other primate. Two and a half million years ago, this creature was already well down the road to becoming human.

This remarkable fossil — a milestone of human evolution —€” now sits on my office desk. Or rather, I should say that a 3D printed replica of the fossil sits on my desk.

After printing a few test objects —€” trinkets, really — I quickly settled on this fossil as my first serious print. It was not terribly large, but the complexity of the shape made it a challenging object. I spent a bit of time researching the various printer settings, making choices for things such as the amount of support scaffolding to be used for overhangs, speed of printer head movement, filament temperature, and so on. But as this was my first major attempt at printing, I had no frame of reference, and was forced to more-or-less guess at the settings.

I was very happy to learn that the printer was fairly forgiving of less than optimal configurations, as an excellent result was achieved on my very first attempt.

The resulting object is light, but very solid thanks to its internal honeycomb structure. The surface is smooth, only revealing the layers of the printing if the light catches the surface in just the right way. Best of all, so much of the detail of the original fossil has been captured in my print that I can recognize the near-human features of this creature that originally fascinated me, such as the not-yet fused sutures of the skull, and the imprint of the fontanel on the brain.

My first experience with 3D printers was only two years ago. At that time, printing was a hit-or-miss affair. The printers were extremely finicky, and even the best results were fragile, low-resolution objects that were remarkable for their novelty, but little else. Now, just two years later, the quality of the object I cranked out of our printer was not far from what I would see from commercially produced items. Given this progress, it'€™s easy to imagine routinely repairing things around the house by printing out dishwasher knobs, wall brackets, pins, clips, frames, or any of the other hundred things I wind up breaking.

Of course, I might want to replace something bigger than what my home printer can manage. For items like that, I can imagine a time when I could go down to the local quick-e-print shop, and have them print a new bumper for my car.

Overall, I think it'€™s important to keep in mind that 3D printers have incredible relevance in society today. In fact, a 22-year-old woman had the whole top of her skull replaced with a customized 3D-printed implant. Dr. Bon Verweij of University Medical Center (UMC) Utrecht, whose team carried out the procedure, were the first in the world to replace a complete skull.

"We used to create an implant by hand in the operating theater using a kind of cement, but those implants did not have a very good fit," Verweij said. "Now we can use 3-D printing to ensure that these components are an exact fit. This has major advantages, not only cosmetically but also because patients often have better brain function compared with the old method."

The potential to further develop 3D printers is huge, as is the ability to revolutionize almost everything around us.