[mendort]

Is 3D printing really enabling this? If they can make the measurements, I have a hard time believing that an experienced machinist couldn't fabricate the parts necessary. This seems more like a victory of measurement technologies that allow the requirements for a replacement skull to be precisely mapped, than a triumph of 3d printing. (Though I do admit that 3d printing would probably be a lot cheaper than machining.)

[lwan]

Absolutely. No "experienced machinist" can reasonably make this part within spec. The time and cost for a CNC / operator / programming is exorbitant and simply beyond the reach of most people.

3D printing in this context allows for the fabrication of complex geometries that would be incredibly resource intensive otherwise.

You're correct in proposing that measurement techniques have enabled for this. But what good are the measurements if your tools do not allow for you to produce anything meaningful from the data?

[hrktb]

Somewhere in the middle: "Typically, they use a special type of cement, but those replacements often don't have a good fit because they had to be created by hand."

[bnegreve]

With traditional manufacturing methods, you would need to make a mold. Molds are very expensive unless you can reuse them for thousands of units.