title: Castor oil polyurethane containing silica nanoparticles as filling material of bone defect in rats.
abstract: OBJECTIVE
  To evaluate the biologic behavior of the castor polymer containing silica nanoparticles as a bone substitute in diafisary defect.
  
  
  METHODS
  Twenty seven male Rattus norvegicus albinus Wistar lineage were submitted to bone defect filled with castor oil polymer. Three experimental groups had been formed with nine animals each: (1) castor oil polymer containing only calcium carbonate; (2) castor oil polymer with calcium carbonate and doped with 5% of silica nanoparticles; (3) castor polymer with calcium carbonate doped with 10% of silica nanoparticles; 3 animals of each group were submitted to euthanasia 15, 30 and 60 days after experimental procedure, and their femurs were removed to histological evaluation.
  
  
  RESULTS
  there was bone growth in all the studied groups, with a greater tendency of growth in the group 1. After 30 days all the groups presented similar results. After 60 days a greater amount of fibroblasts, osteoblasts, osteocytes and osteoclasts in group 3 was observed, with integrated activity of 3 kinds of cells involved in the bone activation-reabsorption-formation.
  
  
  CONCLUSIONS
  The castor polymer associated to the silica nanoparticles is biocompatible and allows osteoconduction. The presence of osteoprogenitors cells suggests silica osteoinduction capacity.
authors.affiliation: Health and Development in the West Central Region, Federal University of Mato Grosso do Sul (UFMS), Campo Grande-MS, Brazil. renatosnacer@gmail.com
authors.forename: Renato Silva
authors.initials: RS
authors.lastname: Nacer
authors.forename: Rodrigo Ré
authors.initials: RR
authors.lastname: Poppi
authors.forename: Paulo de Tarso Camilo de
authors.initials: Pde T
authors.lastname: Carvalho
authors.forename: Baldomero Antonio Kato da
authors.initials: BA
authors.lastname: Silva
authors.forename: Alexandre Nakao
authors.initials: AN
authors.lastname: Odashiro
authors.forename: Iandara Schettert
authors.initials: IS
authors.lastname: Silva
authors.forename: José Renato Jurkevicz
authors.initials: JR
authors.lastname: Delben
authors.forename: Angela Antonia Sanches Tardivo
authors.initials: AA
authors.lastname: Delben
mesh_terms: D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects* / Q000502:physiology; D018786:Bone Substitutes / Q000627:therapeutic use*; D002368:Castor Oil / Q000737:chemistry / Q000627:therapeutic use*; D008297:Male; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry*; D010006:Osteoblasts / Q000187:drug effects; D011140:Polyurethanes / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D018786:Bone Substitutes; D011140:Polyurethanes; D012822:Silicon Dioxide; D002368:Castor Oil