title: Bone healing in critical-size defects treated with platelet-rich plasma activated by two different methods. A histologic and histometric study in rat calvaria.
abstract: OBJECTIVE
  The purpose of this study was to analyze histologically the influence of platelet-rich plasma (PRP) coagulated with two different activators on bone healing in surgically created critical-size defects (CSD) in rat calvaria.
  
  
  METHODS
  Forty-eight rats were divided into three groups: C, PRP-C and PRP-T. An 8 mm diameter CSD was created in the calvarium of each animal. In group C, the defect was filled by a blood clot only. In groups PRP-C and PRP-T, the defect was filled with PRP activated with either calcium chloride or thromboplastin solution, respectively. Each group was divided into two subgroups (n = 8 per subgroup) and killed at either 4 or 12 weeks postoperatively. Histologic and histometric 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's post hoc test, p < 0.05).
  
  
  RESULTS
  No defect completely regenerated with bone. Group PRP-C had a statistically greater amount of bone formation than groups C and PRP-T at both time points of analysis. No statistically significant differences were observed between groups C and PRP-T.
  
  
  CONCLUSIONS
  It can be concluded that the type of activator used to initiate PRP clot formation influences its biological effect on bone healing in CSD in rat calvaria.
authors.affiliation: Division of Periodontics, Department of Surgery and Integrated Clinic, Dental School of Araçatuba, São Paulo State University-UNESP, Brazil. michel_messora@terra.com.br
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 M
authors.initials: RC
authors.lastname: Dornelles
authors.forename: S R M
authors.initials: SR
authors.lastname: Bomfim
authors.forename: F A C
authors.initials: FA
authors.lastname: Furlaneto
authors.forename: L G N
authors.initials: LG
authors.lastname: de Melo
authors.forename: T M
authors.initials: TM
authors.lastname: Deliberador
authors.forename: A F
authors.initials: AF
authors.lastname: Bosco
authors.forename: V G
authors.initials: VG
authors.lastname: Garcia
authors.forename: S E
authors.initials: SE
authors.lastname: Fucini
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects; D001861:Bone Regeneration / Q000187:drug effects*; D002122:Calcium Chloride / Q000494:pharmacology; D006490:Hemostatics / Q000494:pharmacology*; D008297:Male; D053657:Platelet-Rich Plasma / Q000187:drug effects*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012886:Skull / Q000601:surgery; D013925:Thromboplastin / Q000494:pharmacology
chemical_list: D006490:Hemostatics; D013925:Thromboplastin; D002122:Calcium Chloride