title: Bone healing in critical-size defects treated with platelet-rich plasma: a histologic and histometric study in rat calvaria.
abstract: OBJECTIVE
  The purpose of this study was to analyze histologically the influence of autologous platelet-rich plasma on bone healing in surgically created critical-size defects in rat calvaria.
  
  
  METHODS
  Thirty-two rats were divided into two groups: the control group (group C) and the platelet-rich plasma group. An 8-mm-diameter critical-size defect was created in the calvarium of each animal. In group C the defect was filled by a blood clot only. In the platelet-rich plasma group, 0.35 mL of platelet-rich plasma was placed in the defect and covered by 0.35 mL of platelet-poor plasma. Both groups were divided into subgroups (n = 8) and killed at either 4 or 12 wk postoperatively. Histometric (using image-analysis software) and histologic analyses were performed. The amount of new bone formed was calculated as a percentage of the total area of the original defect. Percentage data were transformed into arccosine for statistical analysis (analysis of variance, Tukey, p < 0.05).
  
  
  RESULTS
  No defect completely regenerated with bone. The platelet-rich plasma group had a statistically greater amount of bone formation than group C at both 4 wk (17.68% vs. 7.20%, respectively) and 12 wk (24.69% vs. 11.65%, respectively) postoperatively.
  
  
  CONCLUSIONS
  Within the limits of this study, it can be concluded that platelet-rich plasma placed in the defects and covered by platelet-poor plasma significantly enhanced bone healing in critical-size defects in rat calvaria.
authors.affiliation: Division of Periodontics, Department of Surgery and Integrated Clinic, Dental School of Araçatuba, São Paulo State University, Brazil.
authors.forename: M R
authors.initials: MR
authors.lastname: Messora
authors.forename: M J H
authors.initials: MJ
authors.lastname: Nagata
authors.forename: R C
authors.initials: RC
authors.lastname: Mariano
authors.forename: R C M
authors.initials: RC
authors.lastname: Dornelles
authors.forename: S R M
authors.initials: SR
authors.lastname: Bomfim
authors.forename: S E
authors.initials: SE
authors.lastname: Fucini
authors.forename: V G
authors.initials: VG
authors.lastname: Garcia
authors.forename: A F
authors.initials: AF
authors.lastname: Bosco
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001861:Bone Regeneration; D007091:Image Processing, Computer-Assisted; D008297:Male; D010976:Platelet Count; D053657:Platelet-Rich Plasma; D011897:Random Allocation; D051381:Rats; D012886:Skull / Q000601:surgery