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3-D Printed Pelvis Holding Up After 3 Years

An anonymous reader writes "Here's a neat story out of Britain, with good news about long-term success for the patient involved, and for others who might benefit from similar procedures: three years ago, surgeon Craig Gerrand successfully printed and implanted an artificial pelvis (actually, about half of one) into a patient suffering from a rare form of cancer. Other techniques were ruled out, because the patient would be losing so much bone. So, after careful scanning, additive printing with titanium was used to create the replacement: 'In order to create the 3-D printed pelvis, the surgeons took scans of the man's pelvis to take exact measurements of how much 3-D printed bone needed to be produced and passed it along to Stanmore Implants. The company used the scans to create a titanium 3-D replacement, by fusing layers of titanium together and then coating it with a mineral that would allow the remaining bone cells to attach.' Now, three years after the procedure, the printed pelvis is holding up just fine, and the patient is able to walk with a cane."

47 of 82 comments (clear)

  1. Not plastic, titanium by HuguesT · · Score: 3, Informative

    There is not much difference with respect to physical properties between printed and sintered metal or ceramics. Sintering is a very well established fabrication process combining endurance, flexibility in design and low weight. However, laser-powered, layered construction a.k.a printing allows for even greater flexibility and most importantly one-off fabrication. This is ideally suited to medical applications like this one. However do not expect to be able to do this at home anytime soon.

    1. Re:Not plastic, titanium by ubergeek2009 · · Score: 4, Insightful

      Selective Laser Sintering metal printing although much stronger than typical Fused Deposition Modeling is nowhere near as strong or tough as cast and treated metal components. It has it's place and this is one, but SLS is not great everywhere.

    2. Re:Not plastic, titanium by drinkypoo · · Score: 3, Insightful

      Wiki quote: "Unlike some metal sintering techniques, the parts are fully dense, void-free, and extremely strong."

      Bah. Sintered metal parts are usually both of those first two things. But the parts have an inferior failure mode (and are more likely to fail) when compared to forged due to the fine grain structure, as opposed to a large interlocking grain structure. Large grains are like legos and small grains are like sand. The large grains interlock, the small grains don't.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    3. Re:Not plastic, titanium by advocate_one · · Score: 2
      good enough to make bicycle frames out of and be lighter than the equivalent tube solution?

      I consider bicycles to be a pretty demanding application stress wise...

      --
      Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
    4. Re:Not plastic, titanium by Shimbo · · Score: 2

      Whilst I wouldn't be 100% sure based on a press report, it does appear to be laser fused:

      http://www.telegraph.co.uk/hea...

    5. Re:Not plastic, titanium by CastrTroy · · Score: 1

      Looks to me like very little of that bike was 3D printed. It looks as thought the only part that was 3D printed was a small part that connects the seat post to the rest of the frame, and even that parts looks like it could be produced using traditional methods.

      --

      Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
    6. Re:Not plastic, titanium by X0563511 · · Score: 1

      Far from an expert on the subject: is there any reason why something that was built with sintering can't be brought up to near-melting and cooled, to restructure the lattice?

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    7. Re:Not plastic, titanium by drinkypoo · · Score: 3, Insightful

      Forging is what creates the large, interlocking grain structure. No forging, no large interlocking grains. You do get some benefits from sintering, like extreme regularity. Thus, even though the failure mode is less desirable, you can more reasonably engineer out failure because you have a better expectation of how the part will behave. The only problem is that ounce for ounce it won't behave as well as forged+machined, so you're either going to throw more material at the problem, or you're going to have to do more design work and then use more costly manufacturing processes. There are inexpensive sintering processes which are not substantially different in most ways from casting plastic, and even without incremental deposition techniques you get secondary benefits which also reduce cost like being able to crack the caps off conn rods instead of machining them to match. By combining deposition modeling you can also create shapes which you can't reasonably cast, which makes using sintered metal practical; you can throw more metal at the problem where necessary to increase durability and strength lost by using sintered metal as opposed to forged, but you can also reduce metal in places you couldn't with casting, without machining it away.

      I am also not an expert on this subject, but I've been doing a lot of reading on it recently.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    8. Re: Not plastic, titanium by drinkypoo · · Score: 1

      I've often wondered if you could create a permanent magnet by sintering in a strong magnetic field, but I don't know why you'd get any other results.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    9. Re:Not plastic, titanium by Dcnjoe60 · · Score: 1

      Selective Laser Sintering metal printing although much stronger than typical Fused Deposition Modeling is nowhere near as strong or tough as cast and treated metal components. It has it's place and this is one, but SLS is not great everywhere.

      Of course, in this application, it only needs be be as strong as the bone it is replacing.

    10. Re: Not plastic, titanium by Grishnakh · · Score: 1

      This is titanium, not a ferrous metal. It can't be magnetized.

    11. Re:Not plastic, titanium by Grishnakh · · Score: 1

      This is all well and good, but don't forget the application here: an artificial pelvis. It doesn't have to be super-strong, it only has to be as strong as something made out of living cells and a bunch of calcium. An artificial titanium pelvis taking up the exact same volume as a natural one should easily be stronger, no matter what kind of process is used to make it. It's not like our human bones have strength-to-weight ratios challenging forged titanium.

    12. Re:Not plastic, titanium by X0563511 · · Score: 1

      I had thought quenching (I think is the term) was specifically intended to fix the crystallization. I've seen it done after forgework - before tempering, the metal is uniformly heated to a quite-high temperature and cooled a couple of times. This was explained in a way that made me think it was causing the crystallization to change in a way that made it less brittle. Incidentally you can demagnetize (or magnetize) things the same way, because things "loosen up" when heated like that, and as it cools they fixate.

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    13. Re:Not plastic, titanium by X0563511 · · Score: 1

      er, I should point out it was not cooled quickly, it was let to cool on it's own (the oven was on a timer to cycle it on it's own). Very distinct from heating it up and then plunging it into oil, which I believe is tempering?

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    14. Re:Not plastic, titanium by matfud · · Score: 1

      If you read the article you would know that the entire frame was printed.

    15. Re:Not plastic, titanium by smellsofbikes · · Score: 1

      This is purely anecdotal, but the two indie framemakers I know who have worked with 3d printed lugs have both said the lugs broke very quickly and they only used them for prototypes, didn't consider them safe to ride. One said he thought he could make a 3d printed lug (this was stainless steel, through shapeways, silver-soldered to Reynolds SS tubing) that would be durable but he guessed it would weigh about 4x as much as equivalent forged columbus lugs.

      --
      Nostalgia's not what it used to be.
    16. Re: Not plastic, titanium by s13g3 · · Score: 2

      Titanium is paramagnetic, meaning that while it is attracted/reactive to the presence of external magnetic fields, it retains no magnetization of its own when removed from said external field. In this specific usage case, magnetization of the part would not be of concern any more than it would be for any other titanium prosthesis.

      --
      "Inveniemus Viam Aut Faciemus" 'We will find a way... Or we will make one!' --Hannibal of Carthage
    17. Re:Not plastic, titanium by drinkypoo · · Score: 1

      This is all well and good, but don't forget the application here: an artificial pelvis. It doesn't have to be super-strong, it only has to be as strong as something made out of living cells and a bunch of calcium.

      I was answering the question posed, not pondering the ramifications of sintering as it relates to medical prosthetics.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    18. Re:Not plastic, titanium by Jarik+C-Bol · · Score: 1

      shapeways uses some other weird technique for their metal printing. Their website says that metal grains are deposited with a void filler, and comes out with the structure of wet sand, and then the whole thing is moved to a special oven and heated to fuse it. They say that if what you are making can't be sculpted from wet sand, then they won't be able to print it. Somehow, this seems like a far cry from laser sintering.

      --
      I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
  2. Sounds like 3D printing... by SeaFox · · Score: 4, Funny

    ...is getting some hip new applications.
    .
    .
    .
    .
    Okay, everyone. Put down your pitchforks.

    1. Re:Sounds like 3D printing... by RobertLTux · · Score: 1

      http://instantrimshot.com/clas...

      just remember folks this was NOT done on a MakerBot or similar (But just wait like 10 years)

      --
      Any person using FTFY or editing my postings agrees to a US$50.00 charge
    2. Re:Sounds like 3D printing... by Procrasti · · Score: 1

      > ...is getting some hip new applications.

      Shouldn't that be some new hip applications?

  3. Titanium? by diakka · · Score: 2

    Personally, I would have opted for adamantium.

    --
    -- Knowledge shared is power lost. -- Aleister Crowley
    1. Re:Titanium? by gmclapp · · Score: 1

      DF reference (+1)

      --
      Common Sense (+1)
    2. Re:Titanium? by richpoore · · Score: 1

      Don't be so dense.

    3. Re:Titanium? by Grishnakh · · Score: 1

      You don't know that adamantium is magnetic.

      Lead is most certainly non-magnetic (same with copper), yet according to the first X-Men movie, Magneto has no trouble controlling lead bullets.

      In the second movie, he stopped the X-Men's airplane from crashing. Airplanes aren't made from steel, they're made usually from aluminum, another totally non-magnetic substance.

      Apparently, in the X-Men universe, ALL metals are magnetic.

  4. Great by Sulphur · · Score: 2

    Ex-cell-ent. Can he still get an MRI with his implant?

    1. Re:Great by Hadlock · · Score: 1

      Yes, Titanium is not a ferrous material.

      --
      moox. for a new generation.
    2. Re:Great by ubergeek2009 · · Score: 2

      It doesn't need to be ferrous, just conductive to prevent an MRI. However that doesn't mean that he can't get an MRI. Printed composites are not terribly conductive, so that may make it possible, but I cannot know for sure without looking at the literature/testing.

    3. Re:Great by drinkypoo · · Score: 1

      Printed composites are not terribly conductive

      Please do let us know how the conductivity of titanium is affected when it is sintered.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    4. Re:Great by Dcnjoe60 · · Score: 1

      Yes, Titanium is not a ferrous material.

      I have a titanium plate in my neck and while it is not impacted by an MRI (ie not ripped out), the MRI is impacted by it. Images in that area are pretty much worthless

  5. Re:I read the title as... by jimshatt · · Score: 2

    No you didn't.

  6. Re:And how much would that cost in America? by Anonymous Coward · · Score: 1

    Indeed, but you must remember, it's not the treatment itself that is so costly over here. It's all the tacked on state regulations and overhead associated with healthcare that drives up the cost.

    The raw materials cost the same here as they do there. Same thing for the infrastructure, the buildings, the instruments, the mechanical, chemical and other associated support devices and manpower it takes to perform such an operation from end to end, etc. etc. etc. They all cost the same.

    Look at it like this, how much is it to puschase a gallon of gas (petrol, I know) in England vs the US? It's roughly double isn't it?

    How much does a gallon of gas cost in England vs the US? It's the same, roughly. That is gasoline (petrol) is made from oil, and we both pay for this oil on the open market, and it costs the same to us as it does to you. Ditto for manufacturing costs; it's the same basic process over here as it is there, hence the costs to make a gallon of gas (petrol) from that barrel of oil are, wait for it, the same.

    So why do you lot pay 2X the cost to fill your cars up then? That's right, taxes, fees and and other costs coming from state regulation and market interference.

    So we're pretty much both of us fooked then aren't we mate?

  7. We can rebuild him. We have the technology. by Arancaytar · · Score: 2

    (...)

    1. Re:We can rebuild him. We have the technology. by Feyshtey · · Score: 1

      Maybe. But he's still an asshole.

      --
      "But we have to pass the bill so that you can find out what is in it,..." - Nancy Pelosi
  8. Just the beginning by jalvarez13 · · Score: 2

    Look at this: New 3D Printer by MarkForged Can Print With Carbon Fiber Definitely more companies are going to develop products like these...

    Imagine the possibilities it opens for elder and disabled people care. And with the current ageing of the population in developed countries, this will certainly be a huge industry.

  9. Re:Misread by drainbramage · · Score: 2

    Elvis?
    A 3-d printed Elvis is exactly what I thought too!

    --
    No brain, no pain.
  10. Re:And how much would that cost in America? by ElementOfDestruction · · Score: 3, Insightful

    I know I'm feeding a troll, but that's a really great argument. Justifying the backbreaking expense of keeping oneself alive against the cost of fuel in two countries. I suppose if you consider the far more efficient vehicles, the vastly reduced amount of driving required, and the great public transport alternatives the argument kind of doesn't seem as brilliant. But I'm just splitting hairs I suppose.

  11. Misread the Subject by RendonWI · · Score: 1

    Came in for a story on a 3D printed penis, left disappointed.

  12. Re:And how much would that cost in America? by Grishnakh · · Score: 1

    You have no idea what you're talking about.

    An artificial hip joint, made in America, costs around $15000 at an American hospital, even though it only cost a few hundred dollars to make (in America).

    That exact same joint, flown to Belgium and installed at a hospital in Belgium, costs less than USD$1000.

    Are you going to try to tell me that Belgium doesn't have state regulations?

  13. Re:Regulations increase cost? by Grishnakh · · Score: 1

    Europe has much more government than America, and far more regulation, yet healthcare there costs a fraction as much, even when they're using medical devices manufactured in America.

    Explain that one.

  14. Re:And how much would that cost in America? by Anonymice · · Score: 1

    As someone who has lived & travelled across much of the world, the UK's public transport infrastructure, especially within cities, ranks very highly.

  15. Re:And how much would that cost in America? by Grishnakh · · Score: 1

    Belgium has more regulation than America. Things cost much, much less. Hence, regulation is a GOOD thing.

    Are you really that fucking stupid?

  16. Re:Regulations increase cost? by Grishnakh · · Score: 1

    Stupid typical warmongering American. Fuck off and die with your shitty healthcare.

  17. Re:And how much would that cost in America? by 0123456 · · Score: 1

    As someone who has lived & travelled across much of the world, the UK's public transport infrastructure, especially within cities, ranks very highly.

    And, given how bad the UK's 'public transport' (i.e. mostly private companies subsidized by the taxpayer) is, that just shows how much it sucks everywhere else.

  18. Re:Democrats more likely to think astrology is sci by Ungrounded+Lightning · · Score: 1

    Isn't that the study that got debunked because it turmed out the bulk of the people rating astrology as scientific had misread it as "astronomy"?

    If so, it might say more about Democrats' literacy than their their belief in astrology.

    It would also be what is expected, given that the consituency of the Democratic party is heavily weighted toward groups of people who have been the victims of poor public schools.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  19. Re:And how much would that cost in America? by ananamouse · · Score: 1

    Issue is really Regulators vs Lawyers.