Bio-glass material re-grows, replaces cartilage

Researchers have developed a bio-glass material that not only mimics the shock-absorbing and load bearing qualities of real cartilage, but potentially encourages it to re-grow, according to a press release published Thursday by the Imperial College London.

Cartilage is flexible connective tissue found in places such as in joints and between vertebrae in the spine. Compared to other types of connective tissue is not easy to repair.

The bio-glass material developed by the researchers from Imperial College London and the University of Milano-Bicocca consists of silica and a plastic or polymer called polycaprolactone.

It displays cartilage-like properties including being flexible, strong, durable and resilient. It can be made in a biodegradable ink form, enabling the researchers to 3D print it into structures that encourage cartilage cells in the knee to form and grow, the process of which has been demonstrated in test tubes.

The material also displays self-healing properties when it gets damaged, which could make it a more resilient and reliable implant, and easier to 3D print when it is in ink form.

The researchers believe they will be able to engineer synthetic bio-glass cartilage disc implants, which would have the same mechanical properties as real cartilage, but which would not need the metal and plastic devices that are currently available.

Another formulation could improve treatments for those with damaged cartilage in their knee.

The team is aiming to print tiny, biodegradable scaffolds using their bio-glass ink. These bio-degradable scaffolds would provide a template that replicates the structure of real cartilage in the knee.

When implanted, the combination of the structure, stiffness and chemistry of the bio-glass would encourage cartilage cells to grow through microscopic pores, said the researchers. The idea is that over time the scaffold would degrade safely in the body, leaving new cartilage in its place that has similar mechanical properties to the original one.

"Bio-glass has been around since the 1960s, originally developed around the time of the Vietnam War to help heal bones of veterans, which were damaged in conflict. Our research shows that a new flexible version of this material could be used as cartilage-like material," said Prof. Julian Jones from Imperial College London, who is a member of the team.

"We still have a long way to go before this technology reaches patients, but we've made some important steps in the right direction to move this technology towards the marketplace, which may ultimately provide relief to people around the world," said Jones.