title: Guided bone regeneration in osteoporotic conditions following treatment with zoledronic acid.
abstract: OBJECTIVE
  To evaluate new bone formation in calvarial critical size defects (CSD) under dense polytetrafluoroethylene (d-PTFE), microporous membranes for guided bone regeneration (GBR) in healthy, osteoporotic and osteoporotic treated with zoledronic acid (ZA) rats.
  
  
  METHODS
  Forty-eight, female, 6-month old Wistar rats were included in the study. Osteoporosis was induced by ovariectomy (OVX) and calcium-deficient diet in 32 rats. Sixteen OVX rats were treated with a single dose of Zolendronic Acid (ZA) (OZ), while 16 OVX rats received no treatment (O). The remaining 16 rats were sham-operated and used as healthy controls (C). At 6 weeks following osteoporosis induction, two 5 mm CSD were created in the parietal bones and one of them was treated with a double d-PTFE membrane. The healing periods were 30 and 60 days. New bone formation (NB) was assessed by qualitative and quantitative histological analysis.
  
  
  RESULTS
  After 30 days of healing, NB (mean% (95% CI)) was 78.9% (21), 93.1% (9.3) and 84.2% (26.9) in the membrane treated defects and 18.8% (24.1), 27.1% (7.9) and 31% (38.8) in the untreated defects of group O, OZ and C, respectively. After 60 days of healing, NB was 78.3% (14.4), 95.8% (9) and 90.1% (26.1) in the membrane treated defects and 10.8% (17.4), 51.6% (39.4) and 15.7% (12.1) in the untreated defects of group O, OZ and C, respectively. Hierarchical analysis of variance showed that treatment with ZA (P = 0.001) and the use of membrane (P = 0.000) significantly increased new bone formation while presence of osteoporosis may have reduced new bone formation (P = 0.028).
  
  
  CONCLUSIONS
  d-PTFE membranes for GBR promote bone healing in osteoporotic and healthy rats. Treatment with ZA may improve new bone formation in osteoporotic rats.
authors.affiliation: Centre for Adult Oral Health, Institute of Dentistry, Bart's & The London School of Medicine & Dentistry, Queen Mary University, London, UK.
authors.forename: Nikos
authors.initials: N
authors.lastname: Mardas
authors.affiliation: Dental School, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Juliano
authors.initials: J
authors.lastname: Busetti
authors.affiliation: Clinical Department, Dental School, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: José Antonio Poli
authors.initials: JA
authors.lastname: de Figueiredo
authors.affiliation: Department of Dentistry, Federal University of Santa Catarina, Florianópolis, Brazil.
authors.forename: Luis André
authors.initials: LA
authors.lastname: Mezzomo
authors.affiliation: Department of Conservative Dentistry, Dental School, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Roberta Kochenborger
authors.initials: RK
authors.lastname: Scarparo
authors.affiliation: Clinical Oral Research Centre, Institute of Dentistry, Bart's & The London School of Medicine & Dentistry, Queen Mary University, London, UK.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Donos
mesh_terms: D000818:Animals; D050071:Bone Density Conservation Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects*; D004164:Diphosphonates / Q000494:pharmacology / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005260:Female; D007093:Imidazoles / Q000494:pharmacology / Q000627:therapeutic use*; D010024:Osteoporosis / Q000188:drug therapy* / Q000503:physiopathology; D010052:Ovariectomy; D010294:Parietal Bone / Q000473:pathology / Q000502:physiology; D017208:Rats, Wistar; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid
keywords: guided bone regeneration; osteoporosis; rats; zoledronic acid