Feb 9, 2016 
I am continually amazed by the strides modern science is making in saving and improving the lives of patients. Sometimes, it seems like with a little bit of time, miracle cures will soon cease to be science fiction and become science fact. A few years ago, 3D printing was the stuff of Star Trek. Now, 3D printing is literally transforming how medical professionals are treating and changing the lives of their patients. The future of 3D printing in the medical field is most definitely a growing necessity. There seems to be no limit to the creativity and innovations that can come from its continued involvement in medical research, development, and practice.
Let me give a brief overview for those who may be less technologically savvy. The process of 3D printing, as the name implies, entails creating a 3D object from a digital file. A 3D printer operates in much the same way that regular paper printers do, except it uses a resin, fibers, heated metal, or plastic to systematically replicate a physical object designed in specialized 3D imaging software. This software enables 3D designers to create nearly any object or image that can be imagined. As a result, the fashioning of customized medical apparatus has become incredibly easy and accurate. Let's look a little further into how 3D printing is improving and saving lives.
Hearing Devices
Early applications for 3D printing were initially done on a small scale with easily replicated objects. Hearing aids and cochlear implants were easy medical devices to start with due to their small size. Now that 3D printers are being utilized to manufacture these hearing devices, they can be much more accurately customized to fit each unique user. This means easier removal and insertion for the patient and a more comfortable fit. The more fitted hearing aids can also be less visible, making wearing them a little less noticeable, which increases the quality of life for patients who may feel self-conscious about their hearing loss.
Orthopedic Supports
Orthopedic medicine is primarily focused on correcting structural abnormalities or injuries to an individual's skeletal system. Some of these are due to developmental issues that remained uncorrected or became apparent as the patient grew. Developing bowed legs is one of those developmental abnormalities that, if uncorrected, can cause embarrassment and even depression in some patients. Most of the treatments are long and arduous and involve a long hospital stay and metal frames, plates, or implants in the legs. However, orthopedists in Hong Kong have made great strides in both diagnosing and appropriately treating this abnormality by using 3D printing.
As a diagnostic tool, a 3D image of the patient's actual bone is created, and then a physical model of the bone, highlighting the exact areas where the deformity is occurring, is printed. This allows the orthopedist to get a good look at the bone and the issue without exploratory surgery. Usually, the next step after initial diagnosis would be fitting and wearing a metal body frame, and for some patients, that meant wearing the frame for up to a year. Now, with 3D printing, doctors are able to perform surgery to install custom-fit therapeutic orthopedic supports designed specifically to fix that exact patient's bone ailments. This has had stellar results, including a shorter hospital stay and a quicker recovery.
Joint and Bone Replacements
Similarly, 3D printing is also assisting greatly in creating effective replacement joints and spacers for patients who need to replace or repair broken bones or worn-down joints. It's estimated that around a million people undergo hip and knee replacement surgeries every year, and that number just continues to grow due to the fact that the end results provide significant relief from pain and improved quality of life following the procedure. Unfortunately, sometimes, these surgeries fail due to infection; the only way to fix it currently is to have the patient go back in for surgery to remove and then replace the first implant. These secondary surgeries often don't have such a high success rate.
With state-of-the-art tissue engineering being combined with 3D printing, these secondary surgeries have been slowly becoming more effective. Now, temporary spacers laced with antibiotics can be 3D printed in order to fight the infection. Patients are able to walk around with the spacer while the infection is healed. Again, 3D printing allows the spacer to be custom-fitted to the patient, and these can be created with a bioceramic sheath (a kind of man-made bone), making them super-strong and effective.
Dental Work
It used to be that dental implants and molds had to be sent out of the office in order to manufacture permanent crowns and jaw molds in addition to cosmetic dental implants. Now, dentists are using high-quality digital cameras and specialized software to make a 3D image of a patient's jaw, broken tooth, or other dental complaint. The software also is able to quickly create a customized crown on the spot and can be further customized as the dentist requires using computer-aided design. With a click of a mouse, these designs can be sent to an in-office 3D printer and the necessary dental apparatus can be instantaneously made out of dental composite right there. Not only does this vastly shorten the patient's treatment time, but it allows for a better fit for the implant and greater accuracy in creating and designing implants, which limits structural problems or design errors.
Prosthetics
Crafting prosthetics has always been a highly specialized field. An orthotist's primary job is to design, make, and fit these prosthetics to patients. In the past, this meant making a plaster mold of the amputee's leg or arm area and then whittling it down until it was the appropriate size for that patient. This normally produces a lot of waste, which can increase the overall cost for the prosthesis. Now, with the development of 3D printing, this field has taken off, allowing orthotists to create highly specialized customized prosthetics with much more efficiency. These prostheses fit better, are more comfortable to wear, and can increase quality of life through digital color-matching and synthetic-skin coverings to make them less noticeable.
Reconstructive Surgery
Very much in the same way that 3D printing is revolutionizing orthopedic and joint replacement, it's also making a large contribution to facial reconstructive surgery. For those who are in accidents or are born with genetic craniofacial anomalies, 3D printing is transforming their lives. Reconstructive surgeons are now able to model the damage or the anomaly and then have a "dry run" of the surgery as many times as is necessary to get the best outcome for their patients. Usually, a model is taken of the patient's current facial proportions and damage, and then a projected model can also be designed and printed. Even if the surgeries need to be completed in stages (as is often the case with genetic craniofacial anomalies), surgeons can make repeated models to track growth or changes as each round of surgeries is completed. That way, they have a 3D model that can be adjusted or changed as necessary until the patient receives the optimal result.
Cancer Treatments
While 3D printing is not directly used to treat cancer in cancer patients, it is being utilized to increase accuracy in radiation therapy. How? People using 3D printers have created "phantom" tumors and organs based on the actual CT scans taken of patients during treatment. These plastic molds can be filled with liquid, allowing experts to see the effects of radiopharmaceuticals. Radiopharmaceuticals are drugs that contain radioactive material that can be injected into a vein, taken orally, or placed in a body cavity. They are used to treat a number of different tumors, including thyroid cancer, nerve cell cancers, and certain bone cancers. The hope is that the radiopharmaceutical dose will be high enough to kill cancer cells without causing large amounts of damage to the healthy tissue around the tumor site. The accurate modeling of the tumor using 3D printing allows doctors to fine-tune dosing, which can not only increase the effectiveness of the treatment but also lessen the collateral damage to healthy tissue.
Regenerative Medicine
While this technology is still very much in development, incredible strides are being made in being able to print more complex structures, particularly human tissue. Organovo is a San Diego-based company that focuses on regenerative medicine and has been using 3D printers to print functional human tissue for research and regenerative therapies. These printers are currently capable of using "bio-ink" made of living cell mixtures to form living tissue layer by layer.
While printed tissue may seem far away from printing a whole organ, researchers estimate that the technological capability to perform 3D organ-printing is only about 10 years away. This is mind-boggling to me since it seems like this technology is something out of a sci-fi novel, but it is already making massive improvements in assisting with liver tissue research, and if this technology becomes commonplace, it could mean that patients waiting for organ transplants could get genetically matched organs. Considering the thousands of people who die each year waiting for transplant organs, this could save millions of lives.