title: Reconstruction of orbital defect in rabbits with composite of calcium phosphate cement and recombinant human bone morphogenetic protein-2.
abstract: BACKGROUND
  Calcium phosphate cement (CPC) is a biocompatible and osteoconductive bone substitute, and recombinant human bone morphogenetic protein-2 (rhBMP-2) has strong osteoinductibility, therefore we developed a composite bone substitute with CPC and rhBMP-2 and evaluate its reconstruction effect in rabbit orbital defect.
  
  
  METHODS
  Thirty-six rabbits were randomly divided into two groups and a 5 mm × 5 mm × 2 mm bone defect in the infraorbital rim was induced by surgery in each orbit (72 orbits in all). The orbital defects were treated with pure CPC or composite of CPC and rhBMP-2. The osteogenesis ability of different bone substitute was evaluated by gross observation, histological examination, histomorphometrical evaluation, compressive load-to-failure testing, and scanning electron microscope (SEM).
  
  
  RESULTS
  Gross observation showed that both bone substitutes were safe and effective for reconstruction of orbital defect. However, histological examination, histomorphometrical evaluation and SEM showed that CPC/rhBMP-2 group had faster speed in new bone formation and degradation of substitute material than CPC group. Compressive load-to-failure testing showed that CPC/rhBMP-2 group had stronger compressive strength than CPC group at every stage with significant difference (P < 0.05).
  
  
  CONCLUSIONS
  Composite of CPC/rhBMP-2 is an ideal bioactive material for repairing orbital defect, with good osteoconductibility and osteoinductibility.
authors.affiliation: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510060, China. fdhqs@126.com
authors.forename: Yong-Xin
authors.initials: YX
authors.lastname: Zheng
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Hao-Tian
authors.initials: HT
authors.lastname: Lin
authors.forename: Ling
authors.initials: L
authors.lastname: Li
mesh_terms: D000818:Animals; D001843:Bone Cements / Q000627:therapeutic use*; D055396:Bone Morphogenetic Protein 2 / Q000627:therapeutic use*; D018786:Bone Substitutes / Q000627:therapeutic use*; D002130:Calcium Phosphates / Q000627:therapeutic use*; D005260:Female; D008297:Male; D008855:Microscopy, Electron, Scanning; D009915:Orbit / Q000473:pathology / Q000601:surgery* / Q000648:ultrastructure; D010012:Osteogenesis; D011817:Rabbits; D011994:Recombinant Proteins / Q000627:therapeutic use; D019651:Plastic Surgery Procedures / Q000379:methods*; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*
chemical_list: D001843:Bone Cements; D055396:Bone Morphogenetic Protein 2; D018786:Bone Substitutes; D002130:Calcium Phosphates; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; C020243:calcium phosphate