title: Effect of hyperbaric oxygen therapy on tooth extraction sites in rats subjected to bisphosphonate therapy-histomorphometric and immunohistochemical analysis.
abstract: OBJECTIVE
  This study aimed to investigate the effect of hyperbaric oxygen therapy (HBOT) on tooth extraction sites in rats treated with bisphosphonate.
  
  
  METHODS
  Rats were treated with zoledronic acid, subjected to tooth extractions and allocated into groups: (1) 7 days of HBOT, (2) 14 days of HBOT, (3) 7-day control, and (4) 14-day control. The site of tooth extractions was analyzed by histomorphometry and immunohistochemistry.
  
  
  RESULTS
  On macroscopic analysis, HBOT did not significantly affect bone exposure volume either at 7 or 14 days. On hematoxylin and eosin (H&E) analysis, the 14-day HBOT group showed less non-vital bone compared to both controls and 7-day HBOT group. HBOT significantly lowered expression of vascular endothelial growth factor (VEGF), receptor activator NF-kB ligand (RANKL), bone morphogenetic protein-2 (BMP-2), and osteoprotegerin (OPG) at 7 days, compared to control, whereas at 14 days, there was no significant difference for these variables.
  
  
  CONCLUSIONS
  HBOT can reduce the amounts of non-vital bone microscopically detected in tooth extraction sites of rats subjected to bisphosphonate therapy. The effect seems to occur in a dose-dependent mode. Further studies are required to clarify the mechanisms accounting for this effect.
  
  
  CONCLUSIONS
  Treatment of bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been a challenging task, where the effectiveness of HBOT is controversial. This study reports important effects of HBOT on the maxillae of rats subjected to bisphosphonate treatment, making an important contribution to the knowledge about the applicability of HBOT in BRONJ.
authors.affiliation: Postgraduate Program of Dental College, Pontifical Catholic University of Rio Grande do Sul-PUCRS, Porto Alegre, RS, Brazil.
authors.forename: Miguel Luciano
authors.initials: ML
authors.lastname: Silva
authors.affiliation: Postgraduate Program of Biotechnology, Laboratory of Pharmacology, University of Caxias do Sul-UCS, Caxias do Sul, RS, Brazil.
authors.forename: Leandro
authors.initials: L
authors.lastname: Tasso
authors.affiliation: Department of Oncology, Hospital São Lucas, Pontifical Catholic University of Rio Grande do Sul-PUCRS, Porto Alegre, RS, Brazil.
authors.forename: Alan Arrieira
authors.initials: AA
authors.lastname: Azambuja
authors.affiliation: Postgraduate Program of Dental College, Pontifical Catholic University of Rio Grande do Sul-PUCRS, Porto Alegre, RS, Brazil.
authors.forename: Maria Antonia
authors.initials: MA
authors.lastname: Figueiredo
authors.affiliation: Postgraduate Program of Dental College, Pontifical Catholic University of Rio Grande do Sul-PUCRS, Porto Alegre, RS, Brazil.
authors.forename: Fernanda Gonçalves
authors.initials: FG
authors.lastname: Salum
authors.affiliation: Department of Pathology, Hospital São Lucas, Pontifical Catholic University of Rio Grande do Sul-PUCRS, Porto Alegre, RS, Brazil.
authors.forename: Vinicius Duval
authors.initials: VD
authors.lastname: da Silva
authors.affiliation: Postgraduate Program of Dental College, Pontifical Catholic University of Rio Grande do Sul-PUCRS, Porto Alegre, RS, Brazil. karen.cherubini@pucrs.br.|Serviço de Estomatologia, Hospital São Lucas-PUCRS, Av. Ipiranga, 6690/231, Porto Alegre, RS, 90610-000, Brazil. karen.cherubini@pucrs.br.
authors.forename: Karen
authors.initials: K
authors.lastname: Cherubini
mesh_terms: D000818:Animals; D059266:Bisphosphonate-Associated Osteonecrosis of the Jaw / Q000378:metabolism / Q000517:prevention & control*; D050071:Bone Density Conservation Agents / Q000494:pharmacology*; D055396:Bone Morphogenetic Protein 2 / Q000378:metabolism; D004164:Diphosphonates / Q000494:pharmacology*; D006931:Hyperbaric Oxygenation; D007093:Imidazoles / Q000494:pharmacology*; D007150:Immunohistochemistry; D053244:Osteoprotegerin / Q000378:metabolism; D053245:RANK Ligand / Q000378:metabolism; D051381:Rats; D014081:Tooth Extraction; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D000077211:Zoledronic Acid
chemical_list: C525720:Bmp2 protein, rat; D050071:Bone Density Conservation Agents; D055396:Bone Morphogenetic Protein 2; D004164:Diphosphonates; D007093:Imidazoles; D053244:Osteoprotegerin; D053245:RANK Ligand; D042461:Vascular Endothelial Growth Factor A; D000077211:Zoledronic Acid
keywords: Bisphosphonates; Bone; Hyperbaric oxygen therapy; Osteonecrosis