3D Printing for Medical

3D-printed models assist in pre-surgical planning

The innovative use of 3D printing in healthcare is already Improving patient care and experience as well as assisting surgeons in planning and communication. For example, surgeons were able to perform a life-saving surgery on a New York woman who had an unusual type of brain aneurysm. This required intricate pre-surgical planning that could only be achieved with a 3D-printed model due to the complicated twisting of blood vessels. The patient’s brain was scanned before a thermoplastic prototype was printed using polymer to mimic human tissue.

Research involving patients with fractured ankles showed greater satisfaction in pre-operative consultations with doctors who use 3D-printed prototypes of their fractures to explain the details. Using 3D-printed models also led to lowered risk, decreased intraoperative blood loss, increased accuracy and shortened operation times.

3D printing makes medical devices more accessible

Custom-made devices are expensive to produce. These are often needed for patients requiring individualized treatment. While traditional manufacturing is suited for large-scale production, it becomes unviable for the fabrication of one-off or low-volume devices. As such, the industry is turning to additive manufacturing to produce high-quality, unique products at a lower cost.

The FDA approves the 3D printing of medical devices like orthopedic implants, cranial implants, and surgical instruments. These are printed using electron beam melting (EBM) machines that melt superalloy metal powders, like titanium and cobalt-chrome, at high temperatures. This makes high-quality, custom implants accessible.

Suturing or stitching during heart operations can now be automated and performed quickly using suturing devices. This reduces the risk of needlestick injuries suffered by about 240,000 medical staff every year. Parts for suturing instruments are fabricated using direct metal laser melting (DMLM) technology.

Additive manufacturing can also produce one-use, highly specific sterile instruments with complex geometries. On-demand printing helps reduce production and inventory costs while allowing designs to be adapted to individual patients. More precise micro-instruments are now possible when 3D printing is combined with semiconductor technology. 3D printing allows for these complex instruments to be constructed as a single part, thus resolving the common difficulty of parts assembly. One such development is a tiny biopsy forceps that allow for a more accurate biopsy of pancreatic cystic lesions. This is an important step towards a proper diagnosis and treatment of pancreatic cancer.

Fast printing of orthopedic implants

3D printing of custom implants direct from digital information bypasses the long and tedious process of traditional manufacturing. AM processes make it possible to print biocompatible body parts to exact detail. A more precise design leads to reduced complications during implantation and a better outcome for patients. Additive manufacturing using EBM also has the advanced capability of fabricating titanium screws with roughened surfaces. Compared to the traditional smooth screws, these implants encourage better bone fusion.

From polymers to metals and now ceramics, AM’s potential is being explored by researchers at Washington State University who want to create implants with ceramic structures of calcium phosphate (CaP) to support growing bone. By coating titanium-alloy hip and knee implants with 3D-printed ceramic structures, researchers expect these implants to last twice as long as traditional implants.

Bioprinting and 3D printing of synthetic organs

Bioprinting is a new development in 3D printing that makes use of living cells. In 2014, the first bioprinted liver tissue was created and implanted into mice. Pre-clinical data showed the successful integration of tissue. In time, bioprinted liver tissue might be used to treat a range of metabolic defects, including those linked to cystic fibrosis. Bioprinting has since extended to kidney research. In 2017, the first bioprinted kidney tissue was created through a partnership between Murdoch Children’s Research Institute in Melbourne and Organovo.

3D-printed synthetic organs have some way to go before they become a viable option, but their future looks promising. In 2017, researchers in Switzerland demonstrated proof of concept after testing a 3D-printed artificial heart. 3D printed organs could be a temporary life-saving solution for those waiting for an organ donor. 3D-printed organ models can also help surgeons plan surgical procedures or be used in drug research without the need for animal testing.

Functioning 3D-printed biomaterials

There are various techniques in bioprinting. One such technique uses living cells as the base material combined with liquids that deliver essential nutrients and oxygen. A different technique may be used to create scaffolds with minute details that promote tissue and joint regeneration. Yet another form of bioprinting produces functioning blood vessels, bones and heart valves from living tissue.

Researchers at Harvard seek to combine 3D-printed structures with living cells to produce functioning blood vessels capable of delivering nutrients and fluids to human tissue. At the University of California, San Diego, similar 3D-printed blood vessels are being developed that would integrate with the body’s circulatory system.

At Cornell University, living prosthetics, including heart valves, are being developed in the same way. Already, synthetic heart valves are saving lives but their use is restricted to adults. The Children’s Heart Foundation identifies congenital heart defect as the most common birth defect. There is, thus, a significant need for living heart valves to save the lives of younger patients.