Researchers at Northwestern University, the same institute behind this month’s 3D printed hyperelastic bones, have now managed to 3D print bio-degradable stents. The tubes that are usually used to treat narrow or weak arteries, have been fabricated out of a citrus-based polymer. As a man-made structure the stents have the potential to be loaded with anti-coagulant, therefore limiting the risk of complications when used in the body.
Engineers behind the discovery, Guillermo Ameer and Cheng Sun, have used stereo-lithography at a micro level to make the stent, in a process termed micro continuous liquid interface production (microCLIP). This technique allows an accuracy that usually relies solely upon a surgeon’s experience to be effective, as Ameer explained in a press release:
Right now, the vast majority of stents are made from a metal and have off-the-shelf availability in various size. The physician has to guess which stent size is a good fit to keep the blood vessel open. But we’re all different and results are highly dependent on physician experience, so that’s not an optimal solution.
A complete paper on Ameer and Sun’s research is available through Advanced Materials Technologies. Seen below is a microscopic-level photograph comparison of a stent using the conventional method of fabrication to the one made using microCLIP.
A figure featured in: 3D-Printing Strong High-Resolution Antioxidant Bioresorbable Vascular Stents by Guillermo Ameer and Cheng Sun
As you can see the structure of the 3D printed component is a lot smoother than in regular practice.
The team from Northwestern have also produced a video of the microCLIP, the process takes less than four minutes to fabricate up to 100 components at time – a fraction of the time taken by traditional manufacturing methods.
3D printing or Additive manufacturing is a process of making a three-dimensional solid object of virtually any shape from a digital model. 3D printing is achieved using an additive process, where successive layers of material are laid down in different shapes. 3D printing is also considered distinct from traditional machining techniques, which mostly rely on the removal of material by methods such as cutting or drilling (subtractive processes).
A 3D printer is a limited type of industrial robot that is capable of carrying out an additive process under computer control.
While 3D printing technology has been around since the 1980s, it was not until the early 2010s that the printers became widely available commercially. The first working 3D printer was created in 1984 by Chuck Hull of 3D Systems Corp. Since the start of the 21st century there has been a large growth in the sales of these machines, and their price has dropped substantially. According to Wohlers Associates, a consultancy, the market for 3D printers and services was worth $2.2 billion worldwide in 2012, up 29% from 2011.[
The 3D printing technology is used for both prototyping and distributed manufacturing with applications in architecture, construction (AEC), industrial design, automotive, aerospace, military, engineering, civil engineering, dental and medical industries, biotech (human tissue replacement), fashion, footwear, jewelry, eyewear, education, geographic information systems, food, and many other fields. One study has found that open source 3D printing could become a mass market item because domestic 3D printers can offset their capital costs by enabling consumers to avoid costs associated with purchasing common household objects.
3D Printable Models
3D printable models may be created with a computer aided design package or via 3D scanner. The manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting. 3D scanning is a process of analyzing and collecting data of real object; its shape and appearance and builds digital, three dimensional models.