title: The synergistic effect of hierarchical micro/nano-topography and bioactive ions for enhanced osseointegration.
abstract: Both surface chemistry and topography have significant influence on good and fast osseointegration of biomedical implants; the main goals in orthopeadic, dental and maxillofacial surgeries. A surface modification strategy encompassing the use of bioactive trace elements together with surface micron/nano-topographical modifications was employed in this study in an attempt to enhance the osseointegration of Ti alloy (Ti-6Al-4V), a commonly used implant. Briefly, we developed strontium-substituted hardystonite (Sr-HT) ceramic coating with a hierarchical topography where the nanosized grains were superimposed in the micron-rough coating structure. Its ability to induce new bone formation was evaluated by an in vivo animal model (beagle dogs). Hardystonite (HT), classic hydroxyapatite (HAp) coated and uncoated Ti-alloy implants were parallelly investigated for comparison. In addition, we investigated the effects of surface topography and the dissolution products from the coatings on the in vitro bioactivity using canine bone marrow mesenchymal stem cells (BMMSCs) cultured on the implant surface as well as using extracts of the coated implants. Micro-CT evaluation, histological observations, biomechanical test (push-out test) and sequential ﬂuorescent labeling and histomorphometrical analysis consistently demonstrated that our developed Sr-HT-coated Ti-alloy implants have the highest osseointegration, while the uncoated implants had the lowest. The osseointegration ability of HAp-coated Ti alloy was inferior to that seen for HT- and Sr-HT-coated Ti alloy. We demonstrated that the dissolution products, particularly strontium (Sr) from the Sr-HT-coated implants, enhanced the ALP activity and in vitro mineralization ability, while the micro/nano-topography was more related to the promotion of cell adhesion. Those results suggest that our developed Sr-HT coatings have the potential for future use as coatings for orthopedic/dental and maxillofacial devices.
authors: Department of Prosthodontics, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China.
authors: Wenjie
authors: W
authors: Zhang
authors: Guocheng
authors: G
authors: Wang
authors: Yan
authors: Y
authors: Liu
authors: Xiaobing
authors: X
authors: Zhao
authors: Duohong
authors: D
authors: Zou
authors: Chao
authors: C
authors: Zhu
authors: Yuqin
authors: Y
authors: Jin
authors: Qingfeng
authors: Q
authors: Huang
authors: Jian
authors: J
authors: Sun
authors: Xuanyong
authors: X
authors: Liu
authors: Xinquan
authors: X
authors: Jiang
authors: Hala
authors: H
authors: Zreiqat
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D001696:Biomechanical Phenomena / Q000187:drug effects; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D002516:Ceramics / Q000494:pharmacology; D020099:Coated Materials, Biocompatible / Q000494:pharmacology; D003460:Crystallization; D004285:Dogs; D017886:Durapatite / Q000494:pharmacology; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects; D005455:Fluorescent Antibody Technique; D020007:Implants, Experimental; D019012:Integrin beta1 / Q000378:metabolism; D007477:Ions; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry*; D016348:Osseointegration / Q000187:drug effects*; D015675:Osteocalcin / Q000378:metabolism; D058626:Plasma Gases / Q000494:pharmacology; D013324:Strontium / Q000494:pharmacology; D013499:Surface Properties; D014961:X-Ray Diffraction; D055114:X-Ray Microtomography
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D019012:Integrin beta1; D007477:Ions; D058626:Plasma Gases; D015675:Osteocalcin; D017886:Durapatite; D000469:Alkaline Phosphatase; D013324:Strontium