Recently, a Danish company called Particle
A 3D startup company has developed a custom 3D printed implant that not only attaches to the bone to stimulate natural bone growth, but also slowly disappears after the job is done. This new approach to industrial additives reduces the risk of infection for patients compared with current technologies used to assist bone repair, and the implant’s main material – tricalcium phosphate (TCP) powder known as “bioink” The mixture with fat is also more suitable for the human environment than the polymers or titanium commonly used by surgeons.
The main reason for this advantage is that the chemical composition of TCP is very similar to that of human bones, and it has the advantages of no variability and good biocompatibility. Therefore, it has been used in reconstructive surgeries for many years. But in the past, due to limited manufacturing methods, TCPs often needed to be manually carved by surgeons from solid blocks into the desired implant shape. Now, with the help of 3D printing, medical staff only need to scan the patient’s bones or body parts, and then use CAD computer models to design the most suitable implant for the individual. After successful printing, it can be transported to the hospital. Implantation is performed by a surgeon.
Success is never accidental. As early as a few years ago, Denmark had already made many attempts to combine “TCP” and “3D printing”. In 2017, a team of scientists led by Professor Andersen, a biotechnologist at the University of Southern Denmark (SDU), printed a section of bone using a combination of “TCP powder + fat” and then implanted it into the skull of a mouse. “For the first time in history,” this piece of artificial bone successfully deceived the mouse’s immune system and integrated into the mouse’s native tissue. What’s even better is that later, real bone antioxidant marrow grew inside it.
It is precisely because of the previous successful foundation that this breakthrough success was achieved. Through 3D printing, scientists have created implants that are more porous than traditional implants. Not only do these holes store drugs inside for longer, they also help the implant transform into a vascular scaffold, supporting natural bone growth. As the natural bone grows over the implants, they slowly degrade and disappear. This not only reduces the risk of infection and postoperative complications, but also eliminates the need for a secondary surgery for removal, as is the case with polymer or titanium implants.
Scientists have already tested it on pigs and mice, and the results are very promising. Only 8 weeks after transplantation, new bone marrow and blood vessels have been successfully established. However, there are some disadvantages to using porous TCP to print bones, that is, its compressive strength is much lower than that of some human load-bearing bones (such as thigh bones). It may take several years from printing to reaching pre-surgery strength levels, so How to enhance the compressive strength of printed objects should be an important issue in future medical 3D printing.
Source: Powder Circle
