title: Effect of recombinant human bone morphogenetic protein-4 with carriers in rat calvarial defects.
abstract: BACKGROUND
  Bone morphogenetic proteins (BMPs) are being evaluated as candidates for periodontal and bone regenerative therapy. However, the research on recombinant human bone morphogenetic protein-4 (rhBMP-4) has been insufficient to evaluate its capacity to enhance bone formation and its carrier system. The purpose of this study was to evaluate the bone regenerative effect of rhBMP-4 delivered with an absorbable collagen sponge (ACS) or beta-tricalcium phosphate (beta-TCP). We also compared the potential of beta-TCP to that of ACS as a carrier system for rhBMP-4.
  
  
  METHODS
  Eight-mm calvarial critical-sized defects were created in 100 male Sprague-Dawley rats. The animals were divided into 5 groups of 20 animals each. The defects were treated with rhBMP-4/ACS (rhBMP-4 at 0.05 mg/ml), rhBMP-4/beta-TCP (rhBMP-4 at 0.05 mg/ml), ACS alone, beta-TCP alone, or left untreated for surgical control. The rats were sacrificed at 2 or 8 weeks postsurgery, and the results were evaluated radiodensitometrically, histologically, and histomorphometrically.
  
  
  RESULTS
  The results of radiodensitometric analysis were as follows: the rhBMP-4/ACS and the rhBMP-4/beta-TCP groups were more radiopaque than other groups at both 2 and 8 weeks (P < 0.01). The histologic observations were as follows: in the rhBMP-4/ACS and the rhBMP-4/beta-TCP groups, new bone was evident at the defect sites at 2 weeks and 8 weeks. The results of histomorphometric analysis were as follows: the rhBMP-4/ACS and the rhBMP-4/beta-TCP groups had more bone (%) than other groups at both 2 and 8 weeks (P < 0.01).
  
  
  CONCLUSIONS
  Surgical implantation of rhBMP-4/ACS may be used to support bone regeneration in the rat calvarial critical-sized defect, and rhBMP-4/beta-TCP may be able to regenerate bone in the rat calvarial critical-sized defect without complication. In addition, both ACS and beta-TCP may be considered as available carriers for rhBMP-4.
authors.affiliation: Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, Seoul, Korea.
authors.forename: Seong-Hee
authors.initials: SH
authors.lastname: Ahn
authors.forename: Chang-Sung
authors.initials: CS
authors.lastname: Kim
authors.forename: Hun-Joo
authors.initials: HJ
authors.lastname: Suk
authors.forename: Yong-Jun
authors.initials: YJ
authors.lastname: Lee
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Jung-Kiu
authors.initials: JK
authors.lastname: Chai
authors.forename: Chong-Kwan
authors.initials: CK
authors.lastname: Kim
authors.forename: Soo-Boo
authors.initials: SB
authors.lastname: Han
authors.forename: Kyoo-Sung
authors.initials: KS
authors.lastname: Cho
mesh_terms: D015502:Absorptiometry, Photon; D000818:Animals; D001672:Biocompatible Materials; D015519:Bone Density / Q000187:drug effects; D001847:Bone Diseases / Q000188:drug therapy* / Q000473:pathology; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects*; D002130:Calcium Phosphates; D004337:Drug Carriers; D005781:Gelatin Sponge, Absorbable; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins; D012886:Skull / Q000187:drug effects* / Q000473:pathology
chemical_list: C525809:BMP4 protein, human; D001672:Biocompatible Materials; C525811:Bmp4 protein, rat; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D002130:Calcium Phosphates; D004337:Drug Carriers; D011994:Recombinant Proteins; C485817:beta-tricalcium phosphate; C018392:tricalcium phosphate