title: Synthetic Parathyroid Hormone May Augment Bone Volume in Autogenous Grafts: A Study in Rats.
abstract: BACKGROUND
  Synthetic parathyroid hormone [PTH(1-34)] has been investigated for its benefits on bone healing and osteoporosis treatment; however, there is little information regarding bone grafts. This study therefore investigates the effect of PTH(1-34) on autogenous bone graft healing.
  
  
  METHODS
  Bone grafts were harvested from the calvarium of rats with a trephine bur (3-mm internal diameter) and placed on the cortex near the mandible angle with a titanium screw. Animals were randomly assigned to group 1 (control): subcutaneous injections of saline solution, three times a week (n = 15); group 2: 2 μg/kg PTH(1-34), three times a week (n = 15); and group 3: 40 μg/kg PTH(1-34), three times a week (n = 15). Thirty days postoperatively, the animals were killed, and specimens (implant + bed + graft) were removed and used for undecalcified sections. The following histometric parameters were evaluated: total bone thickness (TT) (bed + gap + graft), graft thickness (GT) (adjacent to the implant), bone-to-implant contact (BIC), and bone area (BA) (within the limits of the threads). Five additional animals were sacrificed immediately after surgery (zero hour) to register bed and graft sizes before healing.
  
  
  RESULTS
  Group 3 showed significantly greater bone gain compared with groups 1 and 2 (TT and GT, P <0.05). In relation to initial thickness (zero hour), groups 1 and 2 showed a total decrease in volume of 15.91% and 20.83%, respectively, whereas group 3 showed a slight bone gain (1.21%). Data analysis revealed a significant difference for group 3 compared with groups 1 and 2 (P <0.01). No differences were observed for BIC and BA (P >0.05).
  
  
  CONCLUSIONS
  Systemic administration of PTH(1-34) augmented bone volume in autogenous grafts.
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: Rodrigo A B
authors.initials: RA
authors.lastname: dos Santos
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: Marcelo S
authors.initials: MS
authors.lastname: Ferreira
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: Carlos Eduardo S
authors.initials: CE
authors.lastname: Mafra
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: Marinella
authors.initials: M
authors.lastname: Holzhausen
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: Luiz Antônio Pugliesi Alves
authors.initials: LA
authors.lastname: de Lima
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: Cláudio
authors.initials: C
authors.lastname: Mendes Pannuti
authors.affiliation: Department of Stomatology, University of São Paulo, São Paulo, Brazil.
authors.forename: João Batista
authors.initials: JB
authors.lastname: César Neto
mesh_terms: D000818:Animals; D064592:Autografts; D016025:Bone Transplantation; D001842:Bone and Bones; D015921:Dental Implants; D016348:Osseointegration; D010281:Parathyroid Hormone; D051381:Rats; D014025:Titanium
chemical_list: D015921:Dental Implants; D010281:Parathyroid Hormone; D014025:Titanium
keywords: Bone regeneration; bone transplantation; dental implants; osseointegration; parathyroid hormone; rats