title: Fabrication of β-tricalcium phosphate composite ceramic sphere-based scaffolds with hierarchical pore structure for bone regeneration.
abstract: Polymer sphere-based scaffolds, which are prepared by bonding the adjacent spheres via sintering the randomly packed spheres, feature uniform pore structure, full three-dimensional (3D) interconnection, and considerable mechanical strength. However, bioceramic sphere-based scaffolds fabricated by this method have never been reported. Due to high melting temperature of bioceramic, only limited diffusion rate can be achieved when sintering the bioceramic spheres, which is far from enough to form robust bonding between spheres. In the present study, for the first time we fabricated 3D interconnected β-tricalcium phosphate ceramic sphere-based (PG/TCP) scaffolds by introducing phosphate-based glass (PG) as sintering additive and placing uniaxial pressure during the sintering process. The sintering mechanism of PG/TCP scaffolds was unveiled. The PG/TCP scaffolds had hierarchical pore structure, which was composed by interconnected macropores (>200 μm) among spheres, pores (20–120 μm) in the interior of spheres, and micropores (1–3 μm) among the grains. During the sintering process, partial PG reacted with β-TCP, forming β-Ca2P2O7; metal ions from PG substituted to Ca2+ sites of β-TCP. The mechanical properties (compressive strength 2.8–10.6 MPa; compressive modulus 190–620 MPa) and porosity (30%–50%) of scaffolds could be tailored by manipulating the sintering temperatures. The introduction of PG accelerated in vitro degradation of scaffolds, and the PG/TCP scaffolds showed good cytocompatibility. This work may offer a new strategy to prepare bioceramic scaffolds with satisfactory physicochemical properties for application in bone regeneration.
authors.affiliation: School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
authors.forename: Fupo
authors.initials: F
authors.lastname: He
authors.forename: Guowen
authors.initials: G
authors.lastname: Qian
authors.forename: Weiwei
authors.initials: W
authors.lastname: Ren
authors.forename: Jiyan
authors.initials: J
authors.lastname: Li
authors.forename: Peirong
authors.initials: P
authors.lastname: Fan
authors.forename: Haishan
authors.initials: H
authors.lastname: Shi
authors.forename: Xuetao
authors.initials: X
authors.lastname: Shi
authors.forename: Xin
authors.initials: X
authors.lastname: Deng
authors.forename: Shanghua
authors.initials: S
authors.lastname: Wu
authors.forename: Jiandong
authors.initials: J
authors.lastname: Ye
mesh_terms: D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects; D018786:Bone Substitutes / Q000737:chemistry* / Q000494:pharmacology; D002130:Calcium Phosphates / Q000737:chemistry*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D019245:Compressive Strength; D005898:Glass / Q000737:chemistry; D051379:Mice; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000737:chemistry; D016062:Porosity; D013818:Thermogravimetry; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D010710:Phosphates; C485817:beta-tricalcium phosphate