For the first time, scientists have been able to study how well synthetic bone grafts withstand the stresses they receive during the daily lives of patients to whom they are implanted, and how quickly they help bone regrowth and repair.
The team in question, which examined in microscopic detail what takes place between the graft and the bone, was coordinated by Gianluca Tozzi, one of the many “brains” that have fled abroad, who after graduating from the University of Bologna is now director of the Zeiss Global Centre at the University of Portsmouth (UK). The researcher hopes the result will help find ways to improve the body’s ability to regrow its own bones and enable orthopedic surgeons to predict the success of a synthetic graft.
“Every three seconds,” Tozzi explained to ScienceDaily. A person incurs a fracture due to bone fragility. In addition to breaking easily, brittle bones are also more difficult to repair, especially when the defect area is large. It is vital to understand what happens at that interface where the bone meets the graft, because then we can better engineer the sophisticated materials used. Bones are very complex biological tissues, and a synthetic bone substitute must have specific requirements to allow blood flow and encourage new bone growth.”.
New generation synthetic grafts have the potential to be resorbed by the body over time, allowing gradual bone regeneration at the site where the defect is, but biomaterials that degrade too quickly do not give enough time for new bone to grow, and those that degrade too slowly can cause mechanical instability at the implant site.
The team succeeded in the feat thanks to a device, located in the Zeiss Global Centre, that performs a special X-ray tomography (synchrotron X-ray computed tomography – SR-XCT): “In this way,” said Tozzi, “we can predict the clinical outcome of biomaterials in a living body, significantly improving our knowledge.
Peña Fernández M, Dall’Ara E et al. Full-Field Strain Analysis of Bone-Biomaterial Systems Produced by the Implantation of Osteoregenerative Biomaterials in an Ovine Model. ACS Biomaterials Science & Engineering 2019 5 (5), 2543-2554.
