title: Sinus augmentation using rhBMP-2/ACS in a mini-pig model: relative efficacy of autogenous fresh particulate iliac bone grafts.
abstract: BACKGROUND
  Implant dentistry in the posterior maxilla often requires bone augmentation. The gold standard, autogenous bone graft, requires additional surgery with associated morbidity, while bone biomaterials may not support relevant bone formation. Recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS), however, induces significant, clinically relevant bone formation in several settings including the maxillary sinus floor.
  
  
  OBJECTIVE
  The objective of this study was to compare local bone formation and osseointegration following maxillary sinus augmentation using rhBMP-2/ACS or a particulate autogenous cancellous bone graft obtained from the iliac crest in conjunction with immediate placement of dental implants.
  
  
  METHODS
  Bilateral sinus augmentation using an extraoral approach including rhBMP-2 (0.43 mg/ml)/ACS or the autogenous bone graft, alternated between left and right sinus cavities in five adult male Yucatan mini-pigs, was performed. Two 12-mm dental implants were inserted into the sinus wall protruding approximately 8 mm into the sinus cavity. Surgical sites were closed and sutured in layers; block biopsies collected for histometric analysis at 8 weeks.
  
  
  RESULTS
  rhBMP-2/ACS induced bone of significantly greater and consistent quality compared with the iliac crest autogenous bone graft; bone density averaging 51.9 ± 3.0% vs. 32.9 ± 2.5% (P = 0.01). However, there were only numerical differences in augmented bone height (9.3 ± 0.5 vs. 8.6 ± 0.7 mm) and bone-implant contact (37.4 ± 3.0% vs. 30.7 ± 5.9%) between treatments.
  
  
  CONCLUSIONS
  rhBMP-2/ACS induces bone of superior quality compared with an iliac crest particulate autogenous cancellous bone graft when used for maxillary sinus augmentation, and should perhaps be considered the new standard for this indication.
authors.affiliation: Laboratory for Applied Periodontal & Craniofacial Regeneration, Departments of Periodontics and Oral Biology, Georgia Health Sciences University College of Dental Medicine, Augusta, GA 30912, USA.
authors.forename: Jaebum
authors.initials: J
authors.lastname: Lee
authors.forename: Cristiano
authors.initials: C
authors.lastname: Susin
authors.forename: Nancy A
authors.initials: NA
authors.lastname: Rodriguez
authors.forename: Jamie
authors.initials: J
authors.lastname: de Stefano
authors.forename: Hari S
authors.initials: HS
authors.lastname: Prasad
authors.forename: Amanda N
authors.initials: AN
authors.lastname: Buxton
authors.forename: Ulf M E
authors.initials: UM
authors.lastname: Wikesjö
mesh_terms: D000818:Animals; D015519:Bone Density; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology*; D016025:Bone Transplantation / Q000379:methods*; D015921:Dental Implants; D007085:Ilium / Q000637:transplantation*; D020007:Implants, Experimental; D008297:Male; D010784:Photomicrography; D011994:Recombinant Proteins / Q000494:pharmacology; D059546:Sinus Floor Augmentation / Q000379:methods*; D013552:Swine; D013556:Swine, Miniature; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014182:Transplantation, Autologous
chemical_list: D055396:Bone Morphogenetic Protein 2; D015921:Dental Implants; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2