title: Association between bisphosphonates and jaw osteonecrosis: a study in Wistar rats.
abstract: BACKGROUND
  This work aimed at determining whether bisphosphonate therapy produces a sufficient condition for jaw osteonecrosis after tooth extraction.
  
  
  METHODS
  Rats were allocated into 3 groups: (1) 11 rats treated with alendronate, (2) 10 rats treated with zoledronic acid, and (3) 10 control rats. The animals were subjected to tooth extractions, and at the end of bisphosphonate therapy, they were humanely killed. Histologic sections of the surgical site were processed and analyzed.
  
  
  RESULTS
  The zoledronic acid group showed higher incidences of osteonecrosis, inflammatory infiltrate, and microorganisms. There was no significant difference for epithelial or connective tissue, root fragments, vital bone, and positive staining for vascular endothelial growth factor (VEGF) among the groups.
  
  
  CONCLUSIONS
  Zoledronic acid is associated with jaw osteonecrosis, whereas alendronate did not produce a condition sufficient for osteonecrosis after tooth extraction. Neither zoledronic acid nor alendronate was associated with a reduced immunohistochemical expression of VEGF in vital bone at the tooth extraction site.
authors.affiliation: Postgraduate Program of Dental College, PUCRS, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Marcia P
authors.initials: MP
authors.lastname: Maahs
authors.forename: Alan A
authors.initials: AA
authors.lastname: Azambuja
authors.forename: Maria M
authors.initials: MM
authors.lastname: Campos
authors.forename: Fernanda G
authors.initials: FG
authors.lastname: Salum
authors.forename: Karen
authors.initials: K
authors.lastname: Cherubini
mesh_terms: D019386:Alendronate / Q000008:administration & dosage / Q000009:adverse effects*; D000818:Animals; D050071:Bone Density Conservation Agents / Q000009:adverse effects*; D004164:Diphosphonates / Q000008:administration & dosage / Q000009:adverse effects*; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D007093:Imidazoles / Q000008:administration & dosage / Q000009:adverse effects*; D007568:Jaw / Q000187:drug effects* / Q000473:pathology*; D010020:Osteonecrosis / Q000139:chemically induced*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014081:Tooth Extraction / Q000009:adverse effects; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid; D019386:Alendronate