The scientists claim that the invention, tested on rabbits, will be particularly beneficial for addressing irregularly shaped fractures during surgical procedures.
“As far as I know, there are no known examples in science of using such technology for replacing bone tissue during surgery. This technology is unique,” said biomedical engineer Chung Sin Lee, the lead author of the study, in an interview with Live Science.
Typically, significant fractures or other defects in require bone grafting and metal fixation, such as a rod or plate, to support the broken bone. However, the shape of these implants often does not match the specific fracture of the patient, which can lead to improper healing and decreased bone stability.
Previous studies have shown that it is possible to create custom bone grafts using 3D printing for individual patients. However, their production required significant time and effort, and they could not be used directly during surgery.
What do we know about the new technology?
In a study published in the journal Device, Lee and his colleagues detailed a new method for 3D printing a bone substitute directly onto a fracture using a glue gun. During their work, they successfully tested the technology on rabbits with limb fractures.
In traditional 3D printing, flexible plastic filament is typically used. It is first heated and then shaped as needed. However, Lee and his colleagues created a filament made from two materials: polycaprolactone, which has been used in previous studies to create biodegradable bone scaffolds, and hydroxyapatite, a mineral form of calcium that is crucial for bone structure. The researchers also added two antibiotics to the material to prevent infection; these drugs are released slowly over several weeks.
Using a glue gun modified for low-temperature extrusion of this filament, the researchers first created small shapes that cooled to body temperature within 40 seconds. They then printed 3D bone grafts directly onto fractures and defects during surgeries performed on New Zealand white rabbits (Oryctolagus cuniculus). The team stabilized the fractures with metal plates and screws, and then filled the bone defects with either the specialized bone-like filament or traditional bone cement.
After 12 weeks of monitoring the rabbits’ conditions, the scientists observed remarkable outcomes from their experiment. The animals treated with the new method showed better results (particularly in terms of bone tissue formation and growth) compared to those treated traditionally.
Chung Sin Lee noted, “Further research on larger animals is necessary before the technology can be tested on humans. We believe this approach could find widespread application in the future of trauma surgery.”
Photo: Unsplash