title: Effect of PDGF-BB and beta-tricalcium phosphate (β-TCP) on bone formation around dental implants: a pilot study in sheep.
abstract: OBJECTIVE
  The aim of this investigation was to examine the effect of a combination of purified recombinant human platelet-derived growth factor (rhPDGF-BB) mixed with a synthetic beta-tricalcium phosphate (β-TCP) on bone healing around dental implants with critical size circumferential defects.
  
  
  METHODS
  Three critical size circumferential defects were prepared in the ilium of six sheep. Three dental implants were placed into the centre of each defect and the 3.25 mm circumferential gap was filled with (a) blood clot alone; (b) β-TCP; (c) rhPDGF-BB (0.3 mg/ml) with β-TCP. All the defects in each group were covered with a Bio-Gide(®)  resorbable barrier membrane. The sheep were sacrificed at 2 and 4 weeks and histological and histomorphometric analyses were performed to determine the percentage of new mineralized bone formation and residual β-TCP graft particles in the defects.
  
  
  RESULTS
  Defects filled with rhPDGF-BB/β-TCP showed the highest rate of bone formation after 2 and 4 weeks with limited degradation of the β-TCP particles over 4 weeks. Defects filled with β-TCP showed the least bone fill after 2 and 4 weeks, and faster degradation of the β-TCP particles over 4 weeks compared with defects filled with rhPDGF-BB/β-TCP. Percentage of new mineralized bone was comparable in defects to blood clot alone and β-TCP after 4 weeks of healing, but there was a collapse in the defect area in defects with blood clot alone. In comparison, the space was maintained when β-TCP was used in defects at 4 weeks.
  
  
  CONCLUSIONS
  Defects which had β-TCP alone showed an inhibition in bone healing at 2 and 4 weeks; however, the combination of rhPDGF-BB with β-TCP enhanced bone regeneration in these peri-implant bone defects at the same time intervals.
authors: Colgate Australian Clinical Dental Research Centre, School of Dentistry, University of Adelaide, Australia.
authors: Tina
authors: T
authors: Choo
authors: Victor
authors: V
authors: Marino
authors: P Mark
authors: PM
authors: Bartold
mesh_terms: D000818:Animals; D000077214:Becaplermin; D002130:Calcium Phosphates / Q000494:pharmacology*; D003094:Collagen / Q000494:pharmacology; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D007085:Ilium / Q000601:surgery; D010012:Osteogenesis / Q000187:drug effects*; D020574:Proto-Oncogene Proteins c-sis / Q000494:pharmacology*; D034561:Sheep, Domestic; D014945:Wound Healing
chemical_list: C106416:Bio-Gide; D002130:Calcium Phosphates; D015921:Dental Implants; D020574:Proto-Oncogene Proteins c-sis; C485817:beta-tricalcium phosphate; D000077214:Becaplermin; D003094:Collagen