New bone bonding spheres aim to reduce implant replacement

Researchers at Oxford University’s Department of Materials have devised a new method of coating materials that are to be implanted into bone, resulting in encouraged bone in-growth and bonding while reducing the possibility of loosening implants.

Bone implants are desirable and/or essential in various medical procedures, and are often metallic and secured by an adhesive. Inert materials such as metals do not bond to the surrounding tissue and adhesives eventually degrade, allowing the implant to loosen and leading to the undesirable consequences of implant replacement.

Oxford researchers have addressed this weakness by developing a method of coating the implant so that bone in-growth is encouraged, the bonding is strengthened, and the possibility of loosening is greatly reduced. The coating consists of a phospholipid vesicle surrounded by a hydroxyapitite shell. These spheres are deposited in such a controlled manner in order to build a hierarchical pore structure that encourages bone in-growth.

It is envisaged that the vesicle can also be used to deliver drugs directly to the affected site; in particular, possible applications include using bone morphogenetic proteins to enhance osseointegration, and antibiotics to reduce infection. These coatings could be ideal bone regenerative materials, with the added benefit of being a drug delivery system capable of specifically targeting bone disease.

This discovery is subject to a patent application with Isis Innovation, Oxford University’s technology transfer company. Opportunities are still available for companies interested in developing and utilising this technology.