Artificial Bones
Scientists are creating artificial bones using a modified version of an inkjet printer.
The technology creates perfect replicas of bones that have been damaged and these can then be inserted in the body to help it to heal.
A modified ink-jet printer can be used to directly print layer upon layer of artificial bone for quick-fix grafts used in reconstructive surgery.
The process will revolutionise bone graft surgery, which currently relies on either bits of bone taken from other parts of the body or ceramic-like substitutes.
Repairing Bones
Bone takes a long time to grow and repair, so treating serious damage or carrying out reconstructive procedures can be a slow and painstaking process.
In issue 6 of Advanced Materials, Jake Barralet of the Faculty of Dentistry, at McGill University, (Montréal, Québec) and Uwe Gbureck, Department for Functional Materials in Medicine and Dentistry, University of Würzburg, (Bavaria) and their team describe a method for “printing” artificial bone from the same chemical components as living bone and including biomolecules that trigger blood vessel growth to bring the bone to life after it is implanted in the body.
Cement Paper and Acid Ink
Professor Jake Barralet of McGill University in Montreal, Canada, explained: “The “paper” in our printer is a thin bed of cement-like powder. The inkjets spray the cement with an acid which reacts with it and goes hard.
The McGill – Würzburg team has demonstrated how an artificial bone can be constructed using the minerals brushite and hydroxyapatite instead of conventional “ink” in their printer. By printing one layer on top of another they can build up a highly porous 3D bioceramic material resembling bone at room temperature.
The team also adds natural chemicals to stimulate blood vessel growth – vascular endothelial growth factor (VEGF) or copper sulphate. This allows them to incorporate into their model bone implants the necessary materials for stimulating blood vessel growth and allowing the artificial bone grafts to “grow” into the site being repaired.
It takes only ten minutes for the printer, which is the size of about three filing cabinets, to print a typical bone graft.
Bone Graft
The printed graft acts as a bridge to allow the body to replace the damaged section with new bone. Crucially, the substance created by the printing process contains the same building blocks as real human bone, allowing the graft to eventually dissolve harmlessly into the body.
The sections made by the printer are so precise that spaces can be left to encourage the regrowth of tissue and blood vessels through the graft, mirroring the make-up of normal bone.
Professor Barralet said: “The holes in the bone graft will affect how new bone grows into the graft. ”
Custom Design Fit
“You can design it so you encourage it in a particular direction, to get different tissue repair. It is mainly useful in areas where you need a very good sort of fit, like cosmetic surgery or reconstructive surgery, or in the spine where you don’t want to be playing around to get something to fit.
“We’re a long way from seeing this used in a hospital setting, but it’s an important first step.”
Filed under: Blogroll | Tagged: Artificial Bones, bioceramic material, bone graft surgery, brushite, copper sulphate, hydroxyapatite, Jake Barralet, Uwe Gbureck, vascular endothelial growth factor, VEGF | Leave a comment »