3D printing of bones

If you’re lucky enough to own a working 3D printer, you’ll know how amazing they are. You imagine it, you can print it.

In 2004, a 3D-printed skull was created for a woman who had a chronic bone-thickening disorder that was literally squashing her brain.

Bones are probably the easiest human implantable structures to 3D print, as they are basically just solid structures. Organs and tissues are more difficult.

While bones also usually help to create red blood cells through the marrow contained in the center, if you are just replacing one bone, you should be okay – there is enough marrow in the bones of the entire body that losing a little of it is not going to make much difference.

There are printing materials that can be used to emulate bone so that the body can meld with it easier, such as CT-Bone, which you can print with adjustable porosity so that neighbouring cells can get a good grip on it.

Everyone is shaped different. Some people will have long bones, thick, thin, short, twisted. You can’t create off-the-shelf bone replacements. Every one of them is designed for a specific person. And if that person is young, then it will need to be replaced in a few years as well as the rest of the body grows but the implant doesn’t.

In order to get the shape right, you must scan the existing bone that you intend to replace. Of course, that’s a little tricky, as it’s inside the body and you won’t be able to take it out of the body until after the printing itself is completed, so you need to use a medical scanner.

CT scanning is usually used for scanning bones, and MRI is usually used for scanning tissue. However, CT scans use X-rays, which can be dangerous.

from scan to 3D print. image from http://www.think3d.in

A recent development in scanning is “black bone MRI“, which produces a high contrast image where bone is black (hence the name), and tissue is a much lighter uncontrasted colour. Basically, it makes the bones stand out much more, making it easier for automated processes to use the images to recreate 3D models. Here’s an accessible article on 3D printing with black bone MRI.

Artificial wombs

Extremely premature birth is the leading cause of infant death.

Once a baby is removed from its mother’s womb, you cannot put it back in.

In developed countries, premature babies usually survive because of the level of care we can give them, but there are often problems – under-developed lungs,bleeding on the brain, heart problems, gastrointestinal problems, among others.

And those are just the short-term issues. Long-term issues include  cerebral palsy, impaired cognition, problems with the eyes, ears and teeth, as well as sudden death syndrome.

Scientists recently developed a “bio-bag” which emulates the womb and placenta. While it was so far only been shown to work on preterm lambs, the results are successful, with minimal difference between bio-bag lambs and full-term lambs. Human tests are now feasible.


There are some consequences that this development will have on human life expectancy, apart from the obvious improvement in infant mortality and the lowering of long-term effects as well in those infants.

Imagine you are a pregnant woman and you are sick. Let’s say it’s cancer. You have a choice between taking chemotherapy and possibly killing your unborn child, or waiting for the birth and possibly starting treatment too late, killing yourself and leaving the child mother-less.

What if your doctors offered you the choice of removing the unborn child from your womb and placing it in an artificial womb where it will grow perfectly well until birth, and then you could get your own treatment? Both of you then go on to live happily ever after.

Statistics-based book improvements

Yesterday, I finished the software framework of the website enough that I could put up the text content of each chapter.

I left out the images for now, and will probably need to fix up the references, but it’s basically all there.

As I was copying over the information, I left out one or two chapters because they might not be good enough even for a basic read-through. I left out chapters on nutrition, and on how a person should live if they want to live forever without worrying about money, etc.

I want to talk a little more about the software end of the website, because it’s going to be helping out in the next few years, telling me what pages are the worst in the book.

The basic idea I have is that the measurement of how readable a page is, is how many people clicked from it into the next page.

I’ve broken the book down into chapters and sections. Each section is a stand-alone article discussing a specific topic. For example, the “mathematical universe” in the “quantum immortality” chapter is a defined topic, so can be separated into a whole section on its own.

Each section will have multiple “variations”, with very slight wording changes, image changes, etc. The idea is that visitors to the website will be given a random variation of the section that they want to read, and I will then be able to measure how interesting and readable that variation was, by how many people finished reading it and clicked on “Next” at the bottom to go to the next section (link not yet added at this moment – will add that this evening).

If statistics are kept for hundreds or thousands of reads, then a pretty accurate statement can be said about which section variation is “better” than any other one, because there is a definite goal: the reader should want to go to the next page.

It’s important that the statistics be done over as broad a number of reads as possible, because search engines will read the whole book anyway, as will scrapers, so a larger sample set is needed to help dampen down those effects.

This can be helped, though, by having the statistics-gathering engine only attached to the section using event-based javascript, so if you’re looking at any gathered data, it’s more likely that it describes a human reading the section than a robot.

Another issue is that sometimes someone will come to the book through a search engine for a specific topic, and leave after reading that section. In those cases, how do we know how well written the section was?

The solution I’ll use here is that sections themselves will be broken down into artificial “pages”. If someone clicks through each page of a section, then it’s good, and if a high percentage stop reading at a certain point, then that indicates a page that needs work.

Reading through the pure text of the book at the moment, I know it’s not very good, but I expect that over the next few months, it will improve dramatically.

Live Forever – the blog

This short article is an introduction to what I’m trying to achieve here, and how.

I started writing a book on how to live forever a few years ago, but never got much beyond the first few pages.

It’s becoming more and more probable that the first person to live to two hundred has already been born, so I wanted to create a book that would describe the current state of research, and ideas on how we can achieve full immortality (not just life extension)/

I have enough content in the book now that I can start putting together a website for it.

My idea is that by putting the entire content of the book online, I can use split-testing to try make it better, by carefully analysing what pages of the book lead to people moving onto the next page, etc.

With the book, I am trying to be as factual as possible about everything, with references for everything that might be contentious.

For the most part, the book’s content is general knowledge – don’t smoke, avoid obesity, exercise – but there is a lot of stuff that people don’t know about, and that sounds really crazy (for want of a better word!) at first hearing.

You’ve probably never heard of NAD+, FOXO4 peptides, or telomere lengthening, for example.

These are properly researched methods to keep your body’s cells young. You will have heard, for example, that red wine is good for you because of something called Resveretrol. Well, David Sinclair, the scientist behind that research went on to research something else called NAD. It turns out there is very solid evidence that this extends life in mice, and there are human trials that suggest the same thing. Of course, we live longer than mice, so we won’t be certain of this for a long time, but the evidence is strong enough that Sinclair and his team take the NMN supplement themselves (which increases NAD in your cells).

On the crazy side, I’ve also written about Quantum Immortality – the idea that you cannot die, because there are infinite universes and there will always be at least one in which you (or an exact clone, right down to the memories) will wake up tomorrow – which is not really as mad as it sounds. Especially if you compare it with some ideas that various religions state as fact.