title: Nitrogen-containing bisphosphonate therapy: assessment of the alveolar bone structure in rats - a blind randomized controlled trial.
abstract: This study aimed to assess the effect of zoledronic acid exposure on structures of the alveolar bone of rats. The sample was composed of 42 male Wistar rats. Animals in the T1 and T2 groups received weekly doses of 0.2 mg/kg intraperitoneal zoledronic acid for 3 weeks, while animals in the T3 group received the same treatment for 8 weeks. The control groups C1, C2 and C3 received equivalent doses of saline. The first upper molars of Wistar rats in the C2, T2, C3 and T3 groups were extracted. Cone-beam computerized tomography scans were performed, and the image density was analysed by grey levels. The presence and type of inflammatory infiltrate, vascularization and bone necrosis were assigned by histological qualitative scores. Histomorphometric analysis of bone density was performed in the groups without extraction. No significant differences were found in the bone grey density estimated by grey-level value and histomorphometric analysis between the C1 and T1 groups (P > 0.05). The grey levels in the T3 group were lower (P < 0.05) than in the C3 group, corresponding to the bone defect. Histological assessments showed the presence of bone necrosis in the T3 group and lower levels of bone remodelling in the test groups (T2 and T3) compared to the control groups (C2 and C3). The results of qualitative analyses did not differ significantly between the groups (P > 0.05). Zoledronic acid-exposed animals showed maxillary changes including reduced grey levels, the presence of bone necrosis and a higher prevalence of inflammatory signs.
authors.affiliation: Animal Experimentation Unit, Experimental Pathology Unit, Clinical Hospital of Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors.forename: Viviane N
authors.initials: VN
authors.lastname: Pacheco
authors.affiliation: Animal Experimentation Unit, Experimental Pathology Unit, Clinical Hospital of Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors.forename: Renan
authors.initials: R
authors.lastname: Langie
authors.affiliation: Animal Experimentation Unit, Experimental Pathology Unit, Clinical Hospital of Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors.forename: Adriana
authors.initials: A
authors.lastname: Etges
authors.affiliation: Animal Experimentation Unit, Experimental Pathology Unit, Clinical Hospital of Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors.forename: Deise
authors.initials: D
authors.lastname: Ponzoni
authors.affiliation: Animal Experimentation Unit, Experimental Pathology Unit, Clinical Hospital of Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors.forename: Edela
authors.initials: E
authors.lastname: Puricelli
mesh_terms: D000539:Alveolar Process / Q000187:drug effects* / Q000473:pathology; D000818:Animals; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000473:pathology*; D050071:Bone Density Conservation Agents / Q000009:adverse effects; D004164:Diphosphonates / Q000009:adverse effects*; D004195:Disease Models, Animal; D007093:Imidazoles / Q000009:adverse effects*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014057:Tomography, X-Ray Computed; D014081:Tooth Extraction; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid
keywords: bisphosphonate-associated osteonecrosis of the jaw; bone; bone density conservation agents; zoledronic acid