The 3D-Printed Hyperelastic “Bone”

Written by Helen Tran

3D printing is a process of building a three-dimensional object from a digital model. In order to do so, a type of material is successively layered until a three-dimensional object is formed. 3D printing has been around for a while; however, it had previously only been used in large corporations because it was expensive. 3D printing is now accessible and can create anything ranging from toys and to shower heads [1]. Scientists have even looked into 3D printing to solve problems in the medical field. For instance, scientists and researchers have printed out stem cells, kidney cells, and cancer cells in order to conduct research and further study these cells [2]. They have also developed surgical equipment using 3D printing that have been effective and costs substantially less than stainless steel tools [3]. Bones are also being printed out to be studied as well as for the purpose of possibly surgically implanting the 3D-printed bone into animals and humans.

Dr. Adam E. Jakus, Professor Ramille N. Shah and colleagues from Northwestern University have been using 3D printing to synthesize ‘hyperelastic bone’ that could trigger its own replacement with real bone. The main component of the hyperelastic bone is hydroxyapatite (90%), which is a calcium substance that is similar to the calcium in our bones. Hydroxyapatite is then mixed with a polymer (polycaprolactone) and can rapidly undergo 3D printing at rates up to 275cm^3/hour [4]. What makes the hyperelastic bone material so unique compared to other materials used for 3D printing is that the material can be folded, rolled, and cut. Therefore, its versatility allows precision for different types of bones, yet it is still durable [4]. The bone is able to withstand similar amounts of force compared to a normal bone. This hyperelastic bone was inserted into a mouse, rat, and macaque and the material integrated with surrounding tissues and elicited bone tissue started to regenerate [5]. Compared to other osteoregenerative biomaterials currently available, the hyperelastic bone is more effective, easily synthesized, easily deployed in the operating room, and most importantly, supports new bone growth.

Now that scientists are able to use 3D printing to introduce an osteoregenerative biomaterial that fills in the gaps and addresses the severe deficiencies found in current products, it could possibly inspire the rest of the scientific community and other related fields to utilize 3D printing in many ways. Hopefully, this opens up the possibility to advance in other areas of research and produce even more beneficial technology without the burden of affordability and availability.

References:

1. “What Is 3-D Printing (additive Manufacturing)? – Definition from WhatIs.com.” WhatIs.com. N.p.,   n.d. Web. 27 Oct. 2016.
2. “7 Major Advancements 3D Printing Is Making in the Medical Field.” TFOT. N.p., 20 Mar. 2015. Web. 02 Nov. 2016.
3. “3D-Printing Could Boost Surgery Access In Low-Income Countries.” 3DPrintcom. N.p., 24 June 2014. Web. 02 Nov. 2016.
4. Jakus, A.E., Rutz, A.L., Jordan, S.W., Kannan, A., Mitchel S.M., Yun, C., Kouble, K.D., Yoo, S.C., Whiteley, H.E., Richter, C., Galiano R.D., Hsu, W.K., Stock, S.R., Hsu, E.L. Shah, R.N. 2016. Hyperelastic “bone”: A highly versatile, growth factor-free, oseteoregenerative, scalable, and surgically friendly biomaterial. Science Translational Medicine. Volume 8: 358ra127
5. ​Nature.com. Nature Publishing Group, n.d. Web. 27 Oct. 2016.