title: Age-dependent degradation of the protein adsorption capacity of titanium.
abstract: Reported bone-implant contact percentages are far below the ideal 100%. We tested a hypothesis that the protein adsorption capability of titanium, which is critical to the process of osseointegration, changes over time before its use. Machined, acid-etched, and sandblasted surfaces were prepared and stored under dark ambient conditions for 3 days, 1 week, or 4 weeks. For all surfaces, protein adsorption decreased as the storage time increased, and their decreasing rates were dependent on titanium topography. After 4 weeks, the amounts of albumin and fibronectin adsorbed by the acid-etched surface were only 20% and 35%, respectively, of that adsorbed by the fresh surface after 2 hours of incubation, and remained substantially low even after 24 hours. This time-dependent degradation in protein adsorption of titanium correlated with its naturally decreasing hydrophilicity, which was not observed for the nickel and chromium surfaces, indicating a titanium-specific biological aging.
authors.affiliation: Laboratory for Bone and Implant Sciences, The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA.
authors.forename: N
authors.initials: N
authors.lastname: Hori
authors.forename: W
authors.initials: W
authors.lastname: Att
authors.forename: T
authors.initials: T
authors.lastname: Ueno
authors.forename: N
authors.initials: N
authors.lastname: Sato
authors.forename: M
authors.initials: M
authors.lastname: Yamada
authors.forename: L
authors.initials: L
authors.lastname: Saruwatari
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
mesh_terms: D000327:Adsorption; D000818:Animals; D002244:Carbon; D002417:Cattle; D005353:Fibronectins / Q000378:metabolism*; D008422:Materials Testing; D008854:Microscopy, Electron; D012044:Regression Analysis; D012709:Serum Albumin / Q000378:metabolism*; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium; D017155:Wettability
chemical_list: D005353:Fibronectins; D012709:Serum Albumin; D002244:Carbon; D014025:Titanium