Tag Archives: 3-d printer

How 3-D printers are set to revolutionize heart valves

With the average age of the population on the rise, aortic heart valve replacement is being growingly requested. An expected 850,000 patients will need experience heart valve replacements in 2050. Researchers are anticipating such demand with a new alternative.

Credit: Andy G (Flickr)

 

A group of scientists at ETH Zurich and the South African company Strait Access Technologies are working with 3-D printers in order to manufacture custom-made artificial heart valves, made out of silicone and created in just an hour.

Working with silicone valves means tailoring it more precisely to the patient. Researchers first determine the shape and size of the heart by using computer tomography or magnetic resonance imaging. Then, they can print a valve that is a perfect match to the heart chamber.

In order to avoid any problems with the implant, researchers create a digital model and a computer simulation with a set of images. Safety is also guaranteed by the material compatibility with the human body, as blood can flow normally through the artificial valve.

The 3D-printed valves enable mechanical matching with the host biological tissue. Credit: Fergal Coulter / ETH Zurich

The new silicon valves would allow surgeons to stop using conventional implants, based on animal tissues or polymers combined with metal frames. They have a rigid shape and meant for patients the need to take life-long immunosuppressants to prevent the body from rejecting them.

“The replacement valves currently used are circular, but do not exactly match the shape of the aorta, which is different for each patient,” says Manuel Schaffner, one of the study’s lead authors and former doctoral student of André Studart, Professor for Complex Materials at ETH.

While the conventional valves take several days to be manufactured, the silicone ones can be done in about an hour thanks to the 3-D printers. Scientists need to create a negative impression of the valve, spraying the ink onto it. Then, a printer tough deposits silicone paste to print specific patterns on their surface.

Scientists expect to extend the life of the replacement valves to 10-15 years, which is how long current models last in patients before they need to be exchanged. Nevertheless, it would take at least 10 years before the new artificial valves come into clinical use, as they have to go through clinical trials first.

“It would be marvelous if we could one day produce heart valves that last an entire lifetime and possibly even grow along with the patient so that they could also be implanted in young people as well,” said Schaffner.

The study was published in the journal Matter.

3d-printing-pen

This pen 3-D prints bone directly on site of injury

A handheld bio pen developed in the labs of the University of Wollongong will allow surgeons to design customised implants during surgery. (c)  University of Wollongong

A handheld bio pen developed in the labs of the University of Wollongong will allow surgeons to design customised implants during surgery. (c) University of Wollongong

Medicine and 3-d printing fit together like a glove. Imagine how many transplants and surgical procedures are so difficult to make or downright impossible because you can’t find a matching tissue or body part for the patient at hand. With 3-D printers, you can even make new bones – identical to those modeled from a patient that would require them. Now, researchers at University of Wollongong (UOW), Australia have unveiled a handheld tool, that closely resembles a pen, which doctors can use to locally 3-D print bone on the spot.

A 3-D printing ‘pen’

The bone pen delivers live cells and growth factors directly to the site of injury, like a sort of ‘stem cell’ ink, accelerating the regeneration of functional bone and cartilage. The cell material is confined inside a biopolymer such as alginate (seaweed extract),  while a second gel layer protects it at the outside. While the two layers of gel are combined in the pen head following extrusion and become dispersed upon an area of the doctor’s choosing,  a low powered ultra-violet light source is fixed to the device that solidifies the inks.

“The combination of materials science and next-generation fabrication technology is creating opportunities that can only be executed through effective collaborations such as this,” ACES Director Professor Gordon Wallace said.

“What’s more, advances in 3D printing are enabling further hardware innovations in a rapid manner.”

UOW’s Professor Gordon Wallace and his team at the Australian Research Council Centre of Excellence for Electromaterials Science developed the device.

UOW’s Professor Gordon Wallace and his team at the Australian Research Council Centre of Excellence for Electromaterials Science developed the device.

Once the cells are ‘drawn’ onto the surgery site they will multiply, become differentiated into nerve cells, muscle cells or bone cells and will eventually turn from individual cells into a thriving community of cells in the form of a functioning a tissue, such as nerves, or a muscle.

“This type of treatment may be suitable for repairing acutely damaged bone and cartilage, for example from sporting or motor vehicle injuries. Professor Wallace’s research team brings together the science of stem cells and polymer chemistry to help surgeons design and personalise solutions for reconstructing bone and joint defects in real time,” said Professor Peter Choong, Director of Orthopaedics at St Vincent’s Hospital Melbourne and the Sir Hugh Devine Professor of Surgery, University of Melbourne.