Personalized 3D printing, even in its relative infancy today, has already broken many frontiers in science and engineering. There is just so much potential in creating precision-built items outside huge manufacturing complexes and engineering facilities, and 3D Printing in Healthcare is one area where that potential of 3D can be truly maximised.
In the field of medicine and healthcare, especially, personalized 3D printing technologies could offer a lot of different new treatment options. Some would be advanced applications that may seem straight out of science fiction. And a few others could eventually become revolutionary concepts that could elevate the minimum level of healthcare for all social groups.
Depending on how the technology develops further in the next few years, some of its core uses may even change the way medicine is studied as a whole.
Cost: The Biggest 3D Printing Breakthrough
In the last few decades, we have witnessed the transformation of 3D printing, from its traditional limited large-scale industrial use, to small-scale local deployment in the form of compact, desktop-sized production hardware.
On the tech consumer industry side, companies such as MakerBot started releasing small form factor 3D printers at prices that are several times cheaper than their factory-level counterparts. Costs usually seen within 5-digits are now available in just four. For example, the Replicator 2X, unveiled in 2013, retailed for $2,799 at the time of its release.
Even more groundbreaking, the DIY side of things had RepRap making the biggest splash during the early 2010s, unveiling 3D printers that can be built using only store-bought components, with the entire building schematics available for free. At the time, the total cost of all the components amounted to just about $500, and can build copies of itself later on, making it one of the first commercially available 3D printers.
This trend was the spark that ignited the current revolution in personalized 3D printing today. This inevitably also applies to medicine, determining the course of development for 3D printing concepts in healthcare for the rest of the decade.
Major 3D Printing Applications in Healthcare
3D printing has the inherent advantage of design freedom. If anything can be conceptualized within the base materials used in 3D printing, it can be developed (eventually) to a sufficient completion level. That is why healthcare and all fields of medicine, in general, have converged into these major applications:
(IMPORTANT NOTE: As 3D printing is still very much a new frontier in healthcare, most of the proposed uses for each application only refers to limited use cases. Many of these ideas are still not universally available at the moment.)
1. Highly-customized Prosthetics
As mundane as its applied technologies seem today, developing prosthetic body parts still faces huge production challenges. Each developed prosthetic unit always needs to be tailored specifically for each recipient. This means it cannot be mass-produced, resulting in several weeks or months of delay when a patient orders one. For the same reason, the price of prosthetic body parts is also very expensive. Thus, it becomes an unavailable option for patients who cannot afford the set premium.
3D printing changes all this. Indeed, the components are still tailor-made to the patient. However, there is a wider allowance for design, further increasing the level of customization. Even better, the component is simply printed onto a desktop machine using relatively cheap building components. This significantly speeds up its post-design production process to just a few days or hours, as well as keeping the costs astoundingly low.
In fact, one of the best application scenarios for 3D printers is the creation of prosthetic limbs for children. At such a young age, kids often outgrow their prosthetic limbs very quickly. By just scaling the original design data up and 3D printing another set, you can prepare a fresh new prosthetic limb for a child within just a day’s worth of visual adjustments.
2. Physical Modeling of A Patient’s Body Part
Viewing three-dimensional data within a two-dimensional computer screen is often enough for engineers and scientists to progress with their studies and projects. However, there is still considerable technical merit in recreating these data as actual, tangible, real-life 3D models by printing them.
For example, surgeons can greatly benefit from a physical 3D model that reproduces the patient’s exact body part they are scheduled to operate on. Instead of analyzing sets of flat, 2D photos, the model can be studied at any angle. Any minute procedure, such as an incision, can be replicated with almost perfect accuracy.
Conversely, a 3D model can also be presented to the patients in order to give them a much higher level of detail as certain conditions or procedures are explained.
3D printed models can even be efficiently used during the presentation of specific medical cases, either for a group of healthcare professionals or within a purely academic setting. In fact, this also extends to forensics, where a 3D printed sample of an autopsied body part may be presented during legal hearings or court cases to provide direct, visceral information to the jury.
3. Efficient Replacement of Single-Use Medical Devices
Single-use medical devices are exactly as their name suggests. They are items that are to be used only once and then immediately disposed of afterwards. There are a number of different reasons, but the most prominent is the risk of cross-contamination and eventual ineffective reuse.
While medical facilities often store a considerable amount of supply for these items, developing a dedicated (local) system for 3D printing single-use medical devices could drastically reduce supply dependence, achieving a relative reduction in costs.
In addition, because the devices can also be made on-demand, sudden surges in their use or demand can be easily met. At the very least, eventual supply shortages can be significantly mitigated if the most critically important devices (such as PPEs) can be 3D printed.
Most importantly, perhaps, is that changes can be instantly made in 3D printed medical devices. For example, if certain tweaks are required for specific surgical tools, a simple redesign of the tools’ 3D data should be sufficient. The next copies of the 3D printed tool should already have the changes taken into effect.
Lastly, even if the devices are not to be used in actual medical procedures, 3D printed versions could still be developed on hand to provide instant training tools for medical students.
4. Development of New Drug Delivery Systems
Apart from its action and dosage, the way a drug is administered also determines how efficient it would work. Many drug delivery systems have been developed through the years that provide varying degrees of patient comfort and body absorption efficiency. However, conceptualizing and testing new designs can take a very long time. Worse, developing the infrastructure to mass-produce them could take even longer.
With 3D printing, the biggest hurdle of testing new delivery designs is automatically negated. If the drug is to be administered using a completely revised capsule design, the hardware can simply print out direct prototypes. This can then be directly used to immediately kickstart the 3D printer into full production should some updated design become approved.
Consequently, this design deployment speed advantage would also allow drug dosages themselves to be tailor-made for specific patients, thanks to 3D printing. First, you can create custom-sized pills and tablets, which will be provided regularly to whoever needs that very specific dosage.
Second, and perhaps the more important point, you can create custom drug combinations. Instead of a patient manually checking the dosage of several drugs in one intake, a single pill or tablet that combines all of those drugs within very precisely measured amounts can help regulate his or her intake.
3D printers can be configured to create layers of any material that can easily be separated into individual measuring units. Thus, the concept can be extended to use single living cells, then eventually tissues, as the printing material itself. Bioprinting, as it is called, is the incorporation of additive manufacturing processes to combine cells in order to develop biomedical components.
The most commonly cited example of bioprinting is the artificial manufacture of skin cells. This is especially suitable for patients who require transplantation procedures, such as those who suffered from burn injuries. Producing the skin cells is made outside the printing hardware, with the 3D printer itself only functioning as a “weaving machine” to arrange the skin cells into place.
Another idea is to use different types of cells to replace damaged or older ones that don’t necessarily require unique functions. Cartilages from cows, for example, can be 3D printed within a collagen structure to replace body parts that don’t have muscles, nerves, or blood vessels. The body’s immunity system won’t reject the artificial body part, and it can also be replaced again later when needed.
6. Synthetic Organ Production
The next big step after bioprinting is the recreation of entire organs and represents the ultimate endgame for 3D printing today. The obvious benefit, of course, is unlocking the gateway to solve all transplantation issues we have today.
However, there is one very heavy caveat with the concept: we have yet to achieve anything remotely close to a complete synthetic organ reproduction. The challenge of creating entire organs from scratch goes beyond simply reproducing and aligning particular cell types. Among the many challenges is the issue of motor development, as synthetic organs need to bear similar qualities of strength and growth to the original one.
Hurdles aside, we did achieve significant strides in making this future application occur sooner. For example, in 2019, scientists at the Wyss Institute published an article detailing their achievement in creating a fully-functioning 3D printed heart ventricle complete with blood vessels. Both the issue of muscle training and blood oxygen supply was solved, albeit in a form that is still yet to be technically considered a complete organ.
As of late 2020, more than 100,000 patients in the United States are still on the waiting list for organ donors, despite having performed almost 40,000 successful transplants last year. And each day, at least 17 people die waiting for an organ transplant. Should fully-functional 3D printed organs truly become viable in the near future, we can expect these figures to improve drastically.
Notable Milestones and Use Cases of 3D Printing in Healthcare
Some of the relatively recent achievements (within the last decade) in healthcare-based 3D printing that can give a better idea of the potential of the technology are as follows:
Surgeons Accurately Destroy Tumor using a 3D Printed Model
Roughly five years ago, a child diagnosed with neuroblastoma (tumors growing from underdeveloped nerve cells) had successfully undergone an operation involving a tumor’s systematic destruction, without significant damage to the surrounding tissue.
Before the procedure took place, the team of surgeons at the Sant Joan de Déu Hospital in Barcelona, Spain, first printed a perfect 3D replica of the tumor. This was the “practice dummy” that they used to tackle every single step of the operation.
Neuroblastoma is a rather tricky type of cancer to treat because the tumors always grow around and within blood vessels and arteries. Often, the risk of causing further injury to the patient is just as high should a treatment called for the removal of the tumors.
But because the surgeon team had a chance to practice with 3D printed replicas of the real thing, they were able to collect all of the information they needed to systematically remove the tumor without causing injury to the surrounding blood vessels.
The operation was the very first official record of 3D printing being used for such a specific purpose. Thus it was a very important practical milestone for 3D printing in healthcare.
3D Printed Models that Feel Like the Actual Organ
Pushing the boundaries of 3D printed models further, a team of scientists was able to create a 3D printed model of a heart developed with the same tangible characteristics as the real organ. The achievement was recently published in the journal ACS Biomaterials Science & Engineering in October 2020.
The specific 3D printing technique that they used was called the Freeform Reversible Embedding of Suspended Hydrogels, or FRESH. As the name suggests, the printing material uses a squishy material called alginate, which was chosen for its physical properties closely resembling actual human heart tissue.
Unlike other 3D printed molds, the replica heart was built from an alginate “gelatin mold” where each layer derived from the full 3D image is run through a slicer. Each ventricle, each pathway, and every connected blood vessel was then carved out with remarkable precision.
Aside from standard training and modeling purposes, scientists hope that the FRESH heart can be the stepping stone to a more advanced version, capable of “cellularizing” the entire structure into an actual human heart. Of course, the team doesn’t really expect this to happen anytime soon, but this end goal will affect its development moving forward.
The Open Source 3D Printed Prosthetics Community for Everyone
e-NABLE is perhaps one of the most prominent communities today when it comes to implementing the concept of 3D printed prosthetics. The movement started as a one-time project in 2011 by cosplay enthusiast Ivan Owen. But it eventually became an official community after 2013, when designs for the first 3D printed mechanical hand was freely shared around the world.
Today, e-NABLE offers a free online tool named “Handomatic”, which is used as an initial fitting program requiring the individual recipient’s physical stats. After the tool completes the measurement, a custom design would then be recommended (generated), which can be downloaded for free by the user.
Of course, owning a commercial 3D printer is required before you can use the downloaded 3D data. But compared to ordering prosthetics the traditional way, this is still several thousand times cheaper. It is also faster since the materials are produced locally. Components are also easy to replace, as they could simply be printed again as required.
The Risk of Exclusivity as a Feature
3D printing in healthcare has made huge strides in recent years, and we have seen an increase in use cases and applications. However, there is still a long way to go before the healthcare ecosystem fully embraces 3D printing.
Aside from current technological limitations, one very significant obstacle for 3D printing in healthcare is its implementation. Availability has always been touted as one of the most important innovations in 3D printing.
But as techniques become more advanced and applications become more complex, cost steadily becomes an issue. If one can 3D print their organs freely several decades in the future, would it be ethical to keep it exclusive only to those who can afford the procedure?
Big changes in our society and our government might be the other key requirement that we need before 3D printing becomes perfectly integrated with our current healthcare systems.