title: Evaluation of a Novel HA/ZrO2-Based Porous Bioceramic Artificial Vertebral Body Combined with a rhBMP-2/Chitosan Slow-Release Hydrogel.
abstract: A new HA/ZrO2-based porous bioceramic artificial vertebral body (AVB), carried a recombinant human bone morphogenetic protein-2 (rhBMP-2)/chitosan slow-release hydrogel was prepared to repair vertebral bone defect in beagles. An ionic cross-linking was used to prepare the chitosan hydrogel (CS gel) as the rhBMP-2 slow-release carrier. The vertebral body defects were implanted with the rhBMP-2-loaded AVB in group A, or a non-drug-loaded AVB in group B, or autologous iliac in group C. The encapsulation rate of rhBMP-2 in rhBMP-2-loaded CS gel was 91.88±1.53%, with a drug load of 39.84±2.34 ng/mg. At 6, 12, 24 weeks postoperatively, radiography showed that the bone calluses gradually increased with time in group A, where the artificial vertebral body had completely fused with host-bone at 24 weeks after surgery. In group C, an apparent bone remodeling was occurred in the early stages, and the graft-bone and host-bone had also fused completely at 24 weeks postoperatively. In group B, fusion occurred less than in groups A and C. At 24 weeks after surgery, micro-computed tomography (Micro-CT) revealed that the volume of newly-formed bone in group A was significantly more than in group B (p<0.05). At 24 weeks after surgery, ultra-compressive strengths of the operated segments were 14.03±1.66 MPa in group A, 8.62±1.24 MPa in group B, and 13.78±1.43 MPa in group C. Groups A and C were both significantly higher than group B (p < 0.05). At 24 weeks postoperatively, the hard tissue sections showed that the AVB of group A had tightly fused with host bone, and that pores of the AVB had been filled with abundant nearly mature bone, and that the new bone structured similarly to a trabecular framework, which was similar to that in group C. In contrast, implant fusion of the AVB in group B was not as apparent as group A. In conclusion, the novel HA/ZrO2-based porous bioceramic AVB carried the rhBMP-2-loaded CS gel can promote the repair of bony defect, and induce bone tissue to grow into the pores, which may replace iliac bone grafts as commonly applied in clinical practice.
authors.affiliation: Zhejiang Chinese Medicine University, Hangzhou, China.
authors.forename: Yihui
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Orthopedics, the Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
authors.forename: Renfu
authors.initials: R
authors.lastname: Quan
authors.affiliation: Department of Orthopedics, the Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
authors.forename: Shangju
authors.initials: S
authors.lastname: Xie
authors.affiliation: Department of Orthopedics, the Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Orthopedics, the Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Cao
authors.affiliation: Department of Orthopedics, the Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhuang
authors.affiliation: Zhejiang Chinese Medicine University, Hangzhou, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Guangxing Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, China.
authors.forename: Rongxue
authors.initials: R
authors.lastname: Shao
authors.affiliation: Department of Orthopedics, the Second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou, China.
authors.forename: Disheng
authors.initials: D
authors.lastname: Yang
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology; D001696:Biomechanical Phenomena; D055396:Bone Morphogenetic Protein 2 / Q000737:chemistry* / Q000494:pharmacology; D002516:Ceramics / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D003692:Delayed-Action Preparations; D004285:Dogs; D004337:Drug Carriers / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D021621:Imaging, Three-Dimensional; D008297:Male; D010012:Osteogenesis / Q000187:drug effects; D016062:Porosity; D011994:Recombinant Proteins / Q000737:chemistry / Q000494:pharmacology; D013131:Spine / Q000000981:diagnostic imaging / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000737:chemistry* / Q000494:pharmacology; D055114:X-Ray Microtomography; D015040:Zirconium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D020100:Hydrogels; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; D048271:Chitosan; D017886:Durapatite; D015040:Zirconium; C028541:zirconium oxide