title: Scaffold-based rhBMP-2 therapy in a rat alveolar defect model: implications for human gingivoperiosteoplasty.
abstract: BACKGROUND
  Primary alveolar cleft repair has a 41 to 73 percent success rate. Patients with persistent alveolar defects require secondary bone grafting. The authors investigated scaffold-based therapies designed to augment the success of alveolar repair.
  
  
  METHODS
  Critical-size, 7 x 4 x 3-mm alveolar defects were created surgically in 60 Sprague-Dawley rats. Four scaffold treatment arms were tested: absorbable collagen sponge, absorbable collagen sponge plus recombinant human bone morphogenetic protein-2 (rhBMP-2), hydroxyapatite-tricalcium phosphate, hydroxyapatite-tricalcium phosphate plus rhBMP-2, and no scaffold. New bone formation was assessed radiomorphometrically and histomorphometrically at 4, 8, and 12 weeks.
  
  
  RESULTS
  Radiomorphometrically, untreated animals formed 43 +/- 6 percent, 53 +/- 8 percent, and 48 +/- 3 percent new bone at 4, 8, and 12 weeks, respectively. Animals treated with absorbable collagen sponge formed 50 +/- 6 percent, 79 +/- 9 percent, and 69 +/- 7 percent new bone, respectively. Absorbable collagen sponge plus rhBMP-2-treated animals formed 49 +/- 2 percent, 71 +/- 6 percent, and 66 +/- 7 percent new bone, respectively. Hydroxyapatite-tricalcium phosphate treatment stimulated 69 +/- 12 percent, 86 +/- 3 percent (p < 0.05), and 87 +/- 14 percent new bone, respectively. Histomorphometry demonstrated an increase in bone formation in animals treated with hydroxyapatite-tricalcium phosphate plus rhBMP-2 (p < 0.05; 4 weeks) compared with empty scaffold.
  
  
  CONCLUSIONS
  Radiomorphometrically, absorbable collagen sponge and hydroxyapatite-tricalcium phosphate scaffolds induced more bone formation than untreated controls. The rhBMP-2 added a small but significant histomorphometric osteogenic advantage to the hydroxyapatite-tricalcium phosphate scaffold.
authors: New York, N.Y. From the Institute of Reconstructive Plastic Surgery, New York University School of Medicine, and the Department of Biomaterials and Biomimetics, New York University College of Dentistry.
authors: Phuong D
authors: PD
authors: Nguyen
authors: Clarence D
authors: CD
authors: Lin
authors: Alexander C
authors: AC
authors: Allori
authors: Jeffrey S
authors: JS
authors: Schachar
authors: John L
authors: JL
authors: Ricci
authors: Pierre B
authors: PB
authors: Saadeh
authors: Stephen M
authors: SM
authors: Warren
mesh_terms: D020341:Absorbable Implants; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D001861:Bone Regeneration / Q000187:drug effects / Q000502:physiology; D002130:Calcium Phosphates / Q000494:pharmacology*; D002972:Cleft Palate / Q000601:surgery; D004195:Disease Models, Animal; D005260:Female; D005893:Gingivoplasty / Q000379:methods; D006801:Humans; D008297:Male; D019647:Oral Surgical Procedures / Q000379:methods; D010012:Osteogenesis / Q000187:drug effects* / Q000502:physiology; D010521:Periosteum / Q000601:surgery; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology*; D019651:Plastic Surgery Procedures / Q000379:methods*; D012307:Risk Factors; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
chemical_list: D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D002130:Calcium Phosphates; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; C018392:tricalcium phosphate