title: Comparative studies on ectopic bone formation in porous hydroxyapatite scaffolds with complementary pore structures.
abstract: Vascularized bone grafts were constructed by implanting hydroxyapatite (HA) scaffolds with complementary macro-pore structures into the dorsal muscle of dogs. The relationship between pore structures and ectopic bone formation properties was investigated. Two types of scaffolds with complementary porous structures were fabricated by spherulite-accumulating and porogen-preparing methods, and were named spherulite HA-positive and porogen HA-negative, respectively. After implantation for 1 month, histological observation showed that all the scaffolds were encapsulated by normal muscle tissue and multiple vascular net with cells, indicating excellent biocompatibility and pore interconnectivity of the scaffolds. In the spherulite HA-positive scaffolds, a number of osteoclasts and osteoblasts coupled with new bone tissues were found after 3 and 6 months' implantations, which was better than those in the porogen HA-negative scaffolds. Similarly, the improvement of mechanical properties and the reconstruction of materials in the spherulite HA-positive scaffolds were superior to those in the porogen HA-negative scaffolds. The different ectopic bone formation induced by different macro-pore structures after intramuscular implantation demonstrated the significant effect of macro-pore structures of scaffolds on osteoinduction and vascularization.
authors.affiliation: Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhi
authors.forename: Xiong
authors.initials: X
authors.lastname: Lu
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Li
authors.forename: Ke
authors.initials: K
authors.lastname: Duan
authors.forename: Rongquan
authors.initials: R
authors.lastname: Duan
authors.forename: Yandong
authors.initials: Y
authors.lastname: Mu
authors.forename: Jie
authors.initials: J
authors.lastname: Weng
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000254:growth & development*; D001846:Bone Development / Q000502:physiology*; D018786:Bone Substitutes / Q000032:analysis / Q000138:chemical synthesis*; D004285:Dogs; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D018919:Neovascularization, Physiologic / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D016062:Porosity; D023822:Tissue Engineering / Q000295:instrumentation*; D054457:Tissue Scaffolds
chemical_list: D018786:Bone Substitutes
keywords: Hydroxyapatite porous scaffold; Macro-pore structure; Osteoinduction; Vascularization