An Massachusetts Institute of Technology (MIT) research team that may have found a way to make bone implants less likely to fail using a high-tech adhesive that more securely bonds implants to bone by promoting cell growth between natural and artificial body parts.
In a study published in the June 26 online edition of Science Translational Medicine, the MIT team and its collaborators from several other institutions reported that the implant adhesive — a multilayered coating of ceramic and nanolayers of polymers infused with proteins — worked so well on lab rats that they will soon be ready to test it in humans.
The nanolayers, or super-thin sheets of material, hold therapies such as growth factors
that attract and encourage the formation of bone cells, causing them to firmly attach to the titanium implant. The coated implants required significantly more force to pull free than uncoated ones; indeed, the researchers said the resulting bond is so strong that under stress, the bone would fracture first before the interface with the implant.
The implant coating works like a tiny, elegant machine. The top coating consists of repeating layers, each impossibly thin, that contain the bone growth factor BMP-2. The layers gradually break apart over a period of weeks, releasing BMP-2 into the body. The factor then stimulates stem cells in bone marrow to transform themselves into new bone cells.
The bottom part of the coating is made of a ceramic that mimics bone, thereby attracting bone cells to its surface. This side of the coating is attached to the implant, and recently formed bone cells tend to affix to this ceramic and grow outward, adhering like “superglue” to attach the implant to the bone.