title: Microporous calcium phosphate ceramics driving osteogenesis through surface architecture.
abstract: The presence of micropores in calcium phosphate (CaP) ceramics has shown its important role in initiating inductive bone formation in ectopic sites. To investigate how microporous CaP ceramics trigger osteoinduction, we optimized two biphasic CaP ceramics (i.e., BCP-R and BCP-S) to have the same chemical composition, equivalent surface area per volume, comparable protein adsorption, similar ion (i.e., calcium and phosphate) exchange and the same surface mineralization potential, but different surface architecture. In particular, BCP-R had a surface roughness (Ra) of 325.4 ± 58.9 nm while for BCP-S it was 231.6 ± 35.7 nm. Ceramic blocks with crossing or noncrossing channels of 250, 500, 1000, and 2000 µm were implanted in paraspinal muscle of dogs for 12 weeks. The percentage of bone volume in the channels was not affected by the type of pores (i.e., crossing vs. closed) or their size, but it was greatly influenced by the ceramic type (i.e., BCP-R vs. BCP-S). Significantly, more bone was formed in the channels of BCP-R than in those of BCP-S. Since the two CaP ceramics differed only in their surface architecture, the results hereby demonstrate that microporous CaP ceramics may induce ectopic osteogenesis through surface architecture.
authors.affiliation: Department of Tissue Regeneration, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE, Enschede, The Netherlands; Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China.
authors.forename: Jingwei
authors.initials: J
authors.lastname: Zhang
authors.forename: Davide
authors.initials: D
authors.lastname: Barbieri
authors.forename: Hetty
authors.initials: H
authors.lastname: ten Hoopen
authors.forename: Joost D
authors.initials: JD
authors.lastname: de Bruijn
authors.forename: Clemens A
authors.initials: CA
authors.lastname: van Blitterswijk
authors.forename: Huipin
authors.initials: H
authors.lastname: Yuan
mesh_terms: D000818:Animals; D018786:Bone Substitutes / Q000737:chemistry / Q000494:pharmacology; D002130:Calcium Phosphates / Q000737:chemistry / Q000494:pharmacology; D002516:Ceramics / Q000737:chemistry / Q000494:pharmacology; D004285:Dogs; D006801:Humans; D008297:Male; D008422:Materials Testing; D010012:Osteogenesis / Q000187:drug effects*; D016062:Porosity
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; C020243:calcium phosphate
keywords: bone grafting; calcium phosphate ceramics; microstructure; osteogenesis; surface architecture