title: Bone regeneration in standardized bone defects with autografts or bone substitutes in combination with platelet concentrate: a histologic and histomorphometric study in the mandibles of minipigs.
abstract: OBJECTIVE
  To evaluate the effect of the addition of platelet concentrate (PC) to autografts or bone substitutes on bone regeneration in standardized bone defects.
  
  
  METHODS
  Three standardized bone defects were prepared in both mandibular angles of 12 adult minipigs. The defects were grafted with autograft, anorganic bovine bone, or synthetic beta-tricalcium phosphate (beta-TCP). PC was added to only 1 side. The animals were divided into 4 groups, which were sacrificed at 4 different time points (1, 2, 4, and 8 weeks) for histologic and histomorphometric analysis. The concentrations of platelets and growth factors were measured to identify correlation to the histologic and histomorphometric results.
  
  
  RESULTS
  No correlation was found between platelet count in whole blood and platelet count in PC (r(p) = 0.36). Furthermore, no correlation could be demonstrated between the platelet count of the PC and the concentrations of PDGF-AB (r(p) = -0.27) and TGF-beta (r(p) = 0.34). There were no signs of a stimulating effect of PC on bone formation in combination with autografts or bone substitutes at any time point (P = .89). Addition of PC did not alter the pattern of graft degradation.
  
  
  CONCLUSIONS
  The present study underlines the need for further investigation to identify the optimal concentrations of platelets and combinations of growth factors to achieve a predictable stimulatory effect on bone regeneration. One of the first steps to achieve this goal will be the development of a reliable method for the procurement of PC.
  
  
  CONCLUSIONS
  PC had no impact on bone formation and graft degradation in standardized bone defects in the mandibles of minipigs.
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Switzerland. simon.storgaard@jensen.mail.dk
authors.forename: Simon Storgård
authors.initials: SS
authors.lastname: Jensen
authors.forename: Nina
authors.initials: N
authors.lastname: Broggini
authors.forename: Gernot
authors.initials: G
authors.lastname: Weibrich
authors.forename: Erik
authors.initials: E
authors.lastname: Hjôrting-Hansen
authors.forename: Robert
authors.initials: R
authors.lastname: Schenk
authors.forename: Daniel
authors.initials: D
authors.lastname: Buser
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001792:Blood Platelets; D001861:Bone Regeneration; D018786:Bone Substitutes; D016025:Bone Transplantation; D002130:Calcium Phosphates; D002417:Cattle; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D008334:Mandible / Q000601:surgery; D008903:Minerals; D010976:Platelet Count; D010982:Platelet-Derived Growth Factor / Q000032:analysis; D011897:Random Allocation; D012044:Regression Analysis; D013552:Swine; D013556:Swine, Miniature; D016212:Transforming Growth Factor beta / Q000032:analysis
chemical_list: C077540:Bio-Oss; D018786:Bone Substitutes; D002130:Calcium Phosphates; D008903:Minerals; D010982:Platelet-Derived Growth Factor; D016212:Transforming Growth Factor beta; C485817:beta-tricalcium phosphate; C095477:platelet-derived growth factor AB