title: Bone tissue reactions to biomimetic ion-substituted apatite surfaces on titanium implants.
abstract: The aim of this study was to evaluate the bone tissue response to strontium- and silicon-substituted apatite (Sr-HA and Si-HA) modified titanium (Ti) implants. Sr-HA, Si-HA and HA were grown on thermally oxidized Ti implants by a biomimetic process. Oxidized implants were used as controls. Surface properties, i.e. chemical composition, surface thickness, morphology/pore characteristics, crystal structure and roughness, were characterized with various analytical techniques. The implants were inserted in rat tibiae and block biopsies were prepared for histology, histomorphometry and scanning electron microscopy analysis. Histologically, new bone formed on all implant surfaces. The bone was deposited directly onto the Sr-HA and Si-HA implants without any intervening soft tissue. The statistical analysis showed significant higher amount of bone-implant contact (BIC) for the Si-doped HA modification (P = 0.030), whereas significant higher bone area (BA) for the Sr-doped HA modification (P = 0.034), when compared with the non-doped HA modification. The differences were most pronounced at the early time point. The healing time had a significant impact for both BA and BIC (P < 0.001). The present results show that biomimetically prepared Si-HA and Sr-HA on Ti implants provided bioactivity and promoted early bone formation.
authors.affiliation: Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. ahmed.ballao@gu.se
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Ballo
authors.forename: Wei
authors.initials: W
authors.lastname: Xia
authors.forename: Anders
authors.initials: A
authors.lastname: Palmquist
authors.forename: Carl
authors.initials: C
authors.lastname: Lindahl
authors.forename: Lena
authors.initials: L
authors.lastname: Emanuelsson
authors.forename: Jukka
authors.initials: J
authors.lastname: Lausmaa
authors.forename: Håkan
authors.initials: H
authors.lastname: Engqvist
authors.forename: Peter
authors.initials: P
authors.lastname: Thomsen
mesh_terms: D000818:Animals; D001031:Apatites; D040761:Biomimetic Materials; D018786:Bone Substitutes; D001842:Bone and Bones / Q000378:metabolism*; D020099:Coated Materials, Biocompatible; D008297:Male; D008422:Materials Testing / Q000379:methods; D010012:Osteogenesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012825:Silicon; D013324:Strontium; D013499:Surface Properties; D014025:Titanium
chemical_list: D001031:Apatites; D018786:Bone Substitutes; D020099:Coated Materials, Biocompatible; D014025:Titanium; D013324:Strontium; D012825:Silicon