Bone bonding at natural and biomaterial surfaces.
Bone bonding is occurring in each of us and all other terrestrial vertebrates throughout life at bony remodeling sites. The surface created by the bone-resorbing osteoclast provides a three-dimensionally complex surface with which the cement line, the first matrix elaborated during de novo bone formation, interdigitates and is interlocked. The structure and composition of this interfacial bony matrix has been conserved during evolution across species; and we have known for over a decade that this interfacial matrix can be recapitulated at a biomaterial surface implanted in bone, given appropriate healing conditions. No evidence has emerged to suggest that bone bonding to artificial materials is any different from this natural biological process. Given this understanding it is now possible to explain why bone-bonding biomaterials are not restricted to the calcium-phosphate-based bioactive materials as was once thought. Indeed, in the absence of surface porosity, calcium phosphate biomaterials are not bone bonding. On the contrary, non-bonding materials can be rendered bone bonding by modifying their surface topography. This paper argues that the driving force for bone bonding is bone formation by contact osteogenesis, but that this has to occur on a sufficiently stable recipient surface which has micron-scale surface topography with undercuts in the sub-micron scale-range.
Davies
John E
JE
Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario, Canada M5S 3G9. davies@ecf.utoronto.ca
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D001843:Bone Cements; D016723:Bone Remodeling; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology*; D002130:Calcium Phosphates / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010010:Osteoclasts; D010012:Osteogenesis; D016062:Porosity; D013499:Surface Properties; D013718:Tensile Strength; D014025:Titanium / Q000737:chemistry
D001672:Biocompatible Materials; D001843:Bone Cements; D002130:Calcium Phosphates; C020243:calcium phosphate; D014025:Titanium