title: Cellular behavior on TiO2 nanonodular structures in a micro-to-nanoscale hierarchy model.
abstract: Biological tissues involve hierarchical organizations of structures and components. We created a micropit-and-nanonodule hybrid topography of TiO(2) by applying a recently reported nanonodular self-assembly technique on acid-etch-created micropit titanium surfaces. The size of the nanonodules was controllable by changing the assembly time. The created micro-nano-hybrid surface rendered a greater surface area and roughness, and extensive geographical undercut on the existing micropit surface and resembled the surface morphology of biomineralized matrices. Rat bone marrow-derived osteoblasts were cultured on titanium disks with either micropits alone, micropits with 100-nm nodules, micropits with 300-nm nodules, or micropits with 500-nm nodules. The addition of nanonodules to micropits selectively promoted osteoblast but not fibroblast function. Unlike the reported advantages of microfeatures that promote osteoblast differentiation but inhibit its proliferation, micro-nano-hybrid topography substantially enhanced both. We also demonstrated that these biological effects were most pronounced when the nanonodules were tailored to a diameter of 300nm within the micropits. An implant biomechanical test in a rat femur model revealed that the strength of bone-titanium integration was more than three times greater for the implants with micropits and 300-nm nanonodules than the implants with micropits alone. These results suggest the establishment of functionalized nano-in-microtitanium surfaces for improved osteoconductivity, and may provide a biomimetic micro-to-nanoscale hierarchical model to study the nanofeatures of biomaterials.
authors: 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: Katsutoshi
authors: K
authors: Kubo
authors: Naoki
authors: N
authors: Tsukimura
authors: Fuminori
authors: F
authors: Iwasa
authors: Takeshi
authors: T
authors: Ueno
authors: Lei
authors: L
authors: Saruwatari
authors: Hideki
authors: H
authors: Aita
authors: Wen-An
authors: WA
authors: Chiou
authors: Takahiro
authors: T
authors: Ogawa
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000502:physiology; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D016348:Osseointegration / Q000502:physiology*; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; C009495:titanium dioxide; D014025:Titanium