title: Periodontal repair in dogs: effect of recombinant human bone morphogenetic protein-12 (rhBMP-12) on regeneration of alveolar bone and periodontal attachment.
abstract: OBJECTIVE
  Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been shown to stimulate alveolar bone and cementum formation in periodontal defects but not a functionally oriented periodontal ligament (PDL). Subcutaneous and intramuscular implants of BMP-12 have been shown to induce tendon formation and ligament-like tissue. The objective of this study was to evaluate rhBMP-12 for periodontal regeneration, in particular PDL formation.
  
  
  METHODS
  Six young adult Hound Labrador mongrel dogs were used. Routine supraalveolar periodontal defects were created around the mandibular premolar teeth. Three animals received rhBMP-12(0.04 mg/ml) in an absorbable collagen sponge (ACS) carrier vs. rhBMP-12(0.2 mg/mL)/ACS in contralateral defects. Three animals received rhBMP-12(1.0 mg/ml)/ACS vs. rhBMP-2(0.2 mg/ml)/ACS (total implant volume/defect approximately 1 ml). The animals were euthanized 8 weeks postsurgery and block biopsies were processed for histometric analysis.
  
  
  RESULTS
  Bone regeneration appeared increased in sites receiving rhBMP-2/ACS compared to sites receiving rhBMP-12/ACS. Cementum regeneration was similar comparing sites implanted with rhBMP-2/ACS to sites implanted with rhBMP-12/ACS. In contrast, sites receiving rhBMP-12/ACS exhibited a functionally oriented PDL bridging the gap between newly formed bone and cementum whereas this was a rare observation in sites receiving rhBMP-2/ACS. Ankylosis appeared increased in sites receiving rhBMP-2/ACS compared to those receiving rhBMP-12/ACS.
  
  
  CONCLUSIONS
  The outcomes of this study suggest that rhBMP-12 may have significant effects on regeneration of the PDL. Additional preclinical evaluation is needed to confirm these initial observations prior to clinical application.
authors.affiliation: Laboratory for Applied Periodontal and Craniofacial Regeneration, Department of Periodontology, Temple University School of Dentistry, Philadelphia, PA 19140, USA. wikesjo@comcast.net
authors.forename: Ulf M E
authors.initials: UM
authors.lastname: Wikesjö
authors.forename: Rachel G
authors.initials: RG
authors.lastname: Sorensen
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Kinoshita
authors.forename: X
authors.initials: X
authors.lastname: Jian Li
authors.forename: John M
authors.initials: JM
authors.lastname: Wozney
mesh_terms: D016301:Alveolar Bone Loss / Q000188:drug therapy*; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects / Q000502:physiology; D003739:Dental Cementum / Q000187:drug effects; D004285:Dogs; D006801:Humans; D008297:Male; D010513:Periodontal Ligament / Q000187:drug effects* / Q000502:physiology; D010865:Pilot Projects; D012038:Regeneration / Q000187:drug effects* / Q000502:physiology; D012391:Root Resorption; D016212:Transforming Growth Factor beta
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D016212:Transforming Growth Factor beta