title: Calcium hypochlorite as a dentin deproteinization agent: Microleakage, scanning electron microscopy and elemental analysis.
abstract: OBJECTIVE
  This study investigated the influence of collagen removal with calcium hypochlorite on the surface morphology of acid-etched dentin and on the microleakage of composite restorations. In addition, the elemental composition (EC) of dentin after removal of the collagen fibrils was analyzed.
  
  
  METHODS
  Forty third molars received two cavities and were divided into four groups according to dentin treatment: CTRL-no pre-treatment; Na10-10% NaOCl for 30 s; Ca10-10% CaOCl for 30 s, and Ca15-15% CaOCl for 30 s. The cavities were filled using an acetone-based adhesive system and a resin composite; they were then subjected to thermal cycling for 5,000 cycles, immersed in methylene blue for 4 h and sectioned into 1-mm thick slabs. Two examiners evaluated two slices per tooth using a stereomicroscope and assigned the degree of infiltration (scores 0-3). The data were analyzed using the Kruskal-Wallis (α = 0.05). Four teeth received surface treatment according to the groups and were submitted to SEM and EDS to carry at the EC.
  
  
  RESULTS
  There was no significant difference between the experimental groups (P = 0.533). CaOCl alters the morphology and surface composition of the dentin, resulting in an increase in the amount of calcium in the interface.
  
  
  CONCLUSIONS
  When used prior to an acetone-based adhesive system, CaOCl did not produce any differences in microleakage when compared to the CTRL group or to the Na10 group.
authors.affiliation: Department of Dentistry, School of Dentistry, Imed, Rua Senador Pinheiro, Passo Fundo, Rio Grande do Sul, Brasil.
authors.forename: Michele Bortoluzzi de Conto
authors.initials: MB
authors.lastname: Ferreira
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, University of Passo Fundo, Passo Fundo, Rio Grande do Sul, Brasil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Carlini Júnior
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Serra Gaúcha College-FSG, Rio Grande do Sul, Brasil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Galafassi
authors.affiliation: Department of Chemistry, School of Chemistry, University of Passo Fundo, Passo Fundo, Rio Grande do Sul, Brasil.
authors.forename: Delton Luiz
authors.initials: DL
authors.lastname: Gobbi
mesh_terms: D002118:Calcium / Q000032:analysis / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry* / Q000494:pharmacology; D003094:Collagen / Q000737:chemistry* / Q000187:drug effects; D003804:Dentin / Q000737:chemistry* / Q000187:drug effects; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008963:Molar / Q000737:chemistry / Q000187:drug effects; D010758:Phosphorus / Q000032:analysis / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission
chemical_list: D017610:Calcium Compounds; C004488:calcium hypochlorite; D010758:Phosphorus; D003094:Collagen; D002118:Calcium
keywords: CaOCl; EDS; SEM; collagen; deproteinization; microleakage