title: Effect of silicon doping on bone formation within alumina porous domains.
abstract: The effect of doping a porous bioinert bioceramic with silicon (Si) on tissue ingrowth, differentiation, and osteogenesis was studied using a rat intramedullary model. Alumina tubes (1.3-mm outer diameter, 0.6-mm inner diameter, 15-mm length) doped with Si at nominal concentrations of 0.5 and 5.0 mol % were implanted into femoral medullary canals of female rats for 16 weeks. Tissue formation within the tubes was determined by histology and histomorphometry. Addition of 0.5 mol % Si to alumina stimulated cellular activity at the bone-ceramic interface and impaired osteogenic maturation within the tubes. In contrast, osteogenesis was enhanced in the 5.0 mol % Si-doped alumina tubes. It is considered that effect of Si is related to surface chemistry rather than microstructure. This work demonstrates that doping a bioinert ceramic with small amounts of Si can significantly alter tissue ingrowth, differentiation, and osteogenesis within a porous implant.
authors.affiliation: School of Materials Science and Engineering, Faculty of Science, The University of New South Wales, Sydney, NSW 2052, Australia. cesmp@bath.ac.uk
authors.forename: Moreica B
authors.initials: MB
authors.lastname: Pabbruwe
authors.forename: Owen C
authors.initials: OC
authors.lastname: Standard
authors.forename: Charles C
authors.initials: CC
authors.lastname: Sorrell
authors.forename: C Rolfe
authors.initials: CR
authors.lastname: Howlett
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D000818:Animals; D002454:Cell Differentiation; D005260:Female; D005269:Femur / Q000166:cytology / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D010012:Osteogenesis / Q000187:drug effects*; D016062:Porosity; D051381:Rats; D017207:Rats, Sprague-Dawley; D012825:Silicon / Q000494:pharmacology*
chemical_list: D000537:Aluminum Oxide; D012825:Silicon