Can 3D printers save lives?

This April, a cancer survivor in the United Kingdom became the first ever patient to have his face reconstructed using a 3D printed prosthetic. The cancer had left him with a gaping hole on the left of his face, requiring him to be fed through a tube fitted into his stomach. Surgeons restructured his face using old photographs and a mirror image of the existing portion, then printed the silicon prosthetic.

From fashion to aerospace engineering, 3D printing, also known as Additive Manufacturing, is increasingly used in multiple industries with researchers also finding exciting medical applications for 3D printing in orthopaedics, dentistry and regeneration of organs. Closer home too, laboratories and classrooms are opening up to the medical possibilities offered by 3D printing.

Dr Kartik Bhanushali, director of Navi Mumbai’s Dr DY Patil Dental College, has 100 students learning to use Computer Aided Design (CAD) and 3D printing as part of their course. “We are also designing a course structure that we plan to get certified and thrown open to 300 dental colleges across the country. It is the future,” says Bhanushali. In his clinic, he uses 3D printing technology to prepare temporary ceramic crowns to cap patients’ problematic teeth. Permanent crowns built using 3D printing are some years away. The heavy work is done by grinders. The load-bearing permanent teeth need a metal composite but these aren’t compatible with the printer just yet,” says Bhanushali.

3D printing, which has been around since the late ’80s, involves sending a CAD file sent to a special printer that prints a three-dimensional object, one fine layer at a time. A layer can be as fine as one micron or 0.001mm. The materials used vary from ceramics, plastics to metals.

In 1986, US inventor Charles Hull created the first machine that produced 3-dimensional objects using a printer connected to a computer. Hull’s technology used liquid resin to build the design layer by layer. An ultraviolet light was used to harden the layers fusing them to each other. The printers were expensive and had limitations, hence their use was restricted to industries that used it for prototyping. But advances in the technology have since increased the type of materials used and the efficiency (thinner the layer, more accurate the design) opening the area to more research and applications.

It’s the way forward in orthopaedics
Only in April, Ayishwariya Menon, clinical team manager at Materialise, a 3D printing research and development firm in Malaysia, was in Mumbai to speak to medical practitioners about adopting 3D printing. In orthopaedics, the technology can be used to create customised anatomical models and patient specific instruments based on the patient’s anatomy, taken from a CT scan, which then help plan and carry out a surgery.

“This reduces the guess work for a surgeon in a complicated operation since he or she is able to recreate the exact conditions of the bone beforehand. Surgeons can also prepare jigs, instruments that guide a bone drill, based on the model that will fit real bone accurately,” explains Guruprasad Rao, CEO of Imaginarium, a 3D manufacturing unit in Mumbai. His unit accepts outsourced 3D printing jobs from surgeons and hospitals as well as from fashion and other industries.

The printer can also create implants be it tooth or the mandible (jaw bone). Since the printed implant will be in contact with the body for a long time, the material is required to be bio-compatible so that the body tissues in contact with it do not reject the foreign object or cause an infection. For this purpose the US government-run Food and Drug Administration (FDA) has approved certain materials which fit the bill. This includes ceramics, polymers and metals like titanium.

“Everyone is unique. The technology allows patient-specific treatments, implants and devices. Patient-specific healthcare will grow very quickly because of this,” says Menon. Materialise has also managed to print a titanium lower jaw bone for a patient.

Traditionally reconstructive jaw bone surgery is a carried out using titanium screws and plates.
The 3D printed version allows for more accurate dimensions reducing the time spent in the operation theatre and post-operative recovery.

New research holds promise too. At Washington State University, researchers Dr Susmita Bose and Dr Amit Bandyopadhyay are putting the finishing touches on a system to use a ceramic 3D printed scaffold that will form the support on which bone tissue will grow in patients. The scaffold is made of a porous material that dissolves in the body over time. “Almost 70 per cent of our bones are made up of calcium phosphate. This way, we can control the geometry of the printed bone and the chemical composition. Metallic implants can be used for load-bearing bones,” says Bose, who sees great potential in treating medical trauma cases this way.

The future is here
Dr Narinder Mehra, head of the department of Transplant Immunology & Immunogenetics at AIIMS, New Delhi, says the technology has a long way to go in India but the potential is vast.
“Currently the short supply of kidneys in organ banks is an increasing obstacle. While research is still in its trial phase in Japan, the possibility of bio-printing or printing of live tissue reducing this gap promises that the technology has good scope in transplantation.”

According to Menon, this technology will take at least 20 years to reach hospitals.

Researchers believe this is just the tip of the iceberg. Surgeon Anthony Atala, director of the Wake Forest Institute for Regenerative Medicine, recently demonstrated how 3D printing could someday soon solve the organ-donor problem. His research, which is still in the early stages of testing uses a 3D printer to print thin sheets of living tissue taken. This tissue is taken from patients and made to grow and reconstruct on a scaffold of cells in the form of a kidney. This will help grow a functional kidney for that specific patient.