|Peeling the Layers of Artificial Bone|
High-magnification scanning electron microscopy shows the leg of an osteoblast attaching to the nanosized hydroxyapatite made from CPC.
Research is showing that layered biomaterials may yield stronger and more successful bone implants.
To show efficacy, researchers from the American Dental Association Foundation (ADAF) and the National Institute of Standards and Technology (NIST) layered two types of macroporous paste calcium phosphate cement (CPC) onto bone.
One type is a fiber-reinforced CPC paste that has strong, yet porous characteristics. The second type is a macroporous layer of CPC. New bone grows into the macroporous layer while the fiber-reinforced aspect provides support for the implant. Once new bone is in place, absorbable fibers in the support layer dissolve to promote even more bone ingrowth.
CPCs are water-based pastes of powdered calcium and a phosphate compound that form hydroxyapatite, a material found in natural bone. Currently it is only used in bones that are not load-bearing (such as those in the face and skull).
The new approach mimics the natural bone structure in which a strong layer, called cortical bone, covers and strengthens a weaker, macroporous layer (spongy bone). By copying this structure, the layered process can be used for load-bearing applications (such as jaws).
The research was presented in the September issue of Biomaterials. The U.S. Public Health Service, NIST, and ADAF funded the research.