title: A physical vapor deposition method for controlled evaluation of biological response to biomaterial chemistry and topography.
abstract: The purpose of this study was to characterize a technique to effectively mask surface chemistry without modifying surface topography. A thin layer of titanium was deposited by physical vapor deposition (PVD) onto different biomaterial surfaces. Commercially pure titanium disks were equally divided into three groups. Disks were either polished to a mirror finish, grit blasted with alumina particles, or grit blasted and subsequently plasma sprayed with a commercial grade of hydroxyapatite (HA). A subgroup of each of these treatment types was further treated by masking the entire disk surface with a thin layer of commercially pure titanium deposited by PVD. A comparison of surface topography and chemical composition was carried out between disks within each treatment group. Canine marrow cells were seeded on all disk surfaces to determine the stability of the PVD Ti mask under culture conditions. The PVD process did not significantly alter the surface topography of any samples. The thin titanium layer completely masked the underlying chemistry of the plasma sprayed HA surface and the chemistry of the plasma vapor deposited titanium layer did not differ from that of the commercially pure titanium disks. Aliquots obtained from the media during culture did not indicate any significant differences in Ti concentration amongst the Ti and Ti-masked surfaces. The PVD application of a Ti layer on HA coatings formed a stable, durable, and homogenous layer that effectively masked the underlying surface chemistry without altering the surface topography.
authors.affiliation: Jo Miller Orthopaedic Research Laboratory, McGill University, Montreal, Canada. ahacking@yahoo.com
authors.forename: S A
authors.initials: SA
authors.lastname: Hacking
authors.forename: M
authors.initials: M
authors.lastname: Zuraw
authors.forename: E J
authors.initials: EJ
authors.lastname: Harvey
authors.forename: M
authors.initials: M
authors.lastname: Tanzer
authors.forename: J J
authors.initials: JJ
authors.lastname: Krygier
authors.forename: J D
authors.initials: JD
authors.lastname: Bobyn
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology*; D001854:Bone Marrow Cells / Q000166:cytology; D049109:Cell Proliferation; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible; D004285:Dogs; D004355:Drug Stability; D017886:Durapatite; D066298:In Vitro Techniques; D008422:Materials Testing; D013499:Surface Properties; D014025:Titanium
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D017886:Durapatite; D014025:Titanium