title: Sodium Thiosulfate for Recovery of Bond Strength to Dentin Treated with Sodium Hypochlorite.
abstract: BACKGROUND
  The aim of this study was to evaluate the efficacy of sodium thiosulfate (Na2S2O3) for restoring adhesion to pulp chamber dentin treated with sodium hypochlorite (NaOCl) and EDTA.
  
  
  METHODS
  Sixty-three crowns of bovine incisors were cut to expose the dentin pulp chamber. The specimens were polished and randomly distributed into 9 groups (n = 7) according to the following protocols used: 0.9% sodium chloride for 30 minutes (negative control), 5.25% NaOCl for 30 minutes, 17% EDTA for 3 minutes, and 5.25% NaOCl for 1 minute (positive control). The other groups, after treatments with NaOCl and EDTA, were immersed in 0.5% or 5% Na2S2O3 for 1, 5, and 10 minutes or just immersed in an inert solution for 10 minutes (0.9% sodium chloride). After drying the specimens, Scotchbond Multi-Purpose (3M ESPE, St Paul, MN) was applied to the pulp chamber dentin followed by Filtek Z250 composite (3M ESPE). Six rectangular slabs were obtained from each specimen, and the dentin/resin interface was tested by using a universal testing machine. The resulting data were submitted to 1-way analysis of variance and the Duncan test (P = .05).
  
  
  RESULTS
  There was a significant decrease in bond strength regarding NaOCl and EDTA (P < .05). When 5% Na2S2O3 was used for 10 minutes, the bond strength was found to be statistically equal to the negative control and higher than the positive control (P < .05).
  
  
  CONCLUSIONS
  The use of Na2S2O3 can significantly increase the bond strength of composite resin to NaOCl/EDTA-treated dentin, allowing adhesive restorations to be immediately applied after endodontic treatment.
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Pimentel Corrêa
authors.affiliation: Department of Restorative Dentistry, Passo Fundo Dental School, University of Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil.
authors.forename: Doglas
authors.initials: D
authors.lastname: Cecchin
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: José Flávio Affonso
authors.initials: JF
authors.lastname: de Almeida
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Brenda Paula Figueiredo de Almeida
authors.initials: BP
authors.lastname: Gomes
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Alexandre Augusto
authors.initials: AA
authors.lastname: Zaia
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil. Electronic address: crandiferraz@gmail.com.
authors.forename: Caio Cezar Randi
authors.initials: CC
authors.lastname: Ferraz
mesh_terms: D000134:Acid Etching, Dental; D000269:Adhesives / Q000737:chemistry; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding / Q000379:methods; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000187:drug effects / Q000648:ultrastructure; D003799:Dental Stress Analysis; D003804:Dentin / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D004492:Edetic Acid / Q000008:administration & dosage / Q000009:adverse effects; D007180:Incisor / Q000000981:diagnostic imaging / Q000187:drug effects; D012388:Root Canal Irrigants / Q000494:pharmacology; D012973:Sodium Hypochlorite / Q000008:administration & dosage / Q000009:adverse effects*; D013885:Thiosulfates / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000269:Adhesives; D000975:Antioxidants; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D012388:Root Canal Irrigants; D013885:Thiosulfates; D004492:Edetic Acid; D012973:Sodium Hypochlorite; C017717:sodium thiosulfate
keywords: Antioxidant agent; bond strength; sodium hypochlorite; sodium thiosulfate