title: Influence of Dentin Deproteinization on Bonding Degradation: 1-year Results.
abstract: BACKGROUND
  The decalcification protocol of dentin surface with sodium hypochlorite removes the exposed collagen fibrils and could improve the longevity of the bonding interface. This study evaluated the influence of collagen removal with 10% sodium hypochlorite (10% NaOCl) on the longitudinal shear bond strength (SBS) of adhesives to dentin.
  
  
  METHODS
  Seventy-two extracted human molars were sectioned and the buccal and lingual surfaces were flattened and acid etched with 37% phosphoric acid for 15 seconds. The specimens were divided into six groups (n = 12 teeth - 24 sections), according to adhesive and collagen removal protocol: group 1: UNO Dentastic; group 2: Prime and Bond NT; group 3: Single Bond; group 4: 10% NaOCl + UNO Dentastic; group 5: 10% NaOCl + Prime and Bond NT; group 6: 10% NaOCl + Single Bond. Composite Z100 buildup was prepared, and the SBS test was assessed after 24 hours and 1 year. Data were submitted to three-way analysis of variance (ANOVA) and Tukey tests (p < 0.05).
  
  
  RESULTS
  The mean values (MPa) were for 24 hours: G1: 22.45B; G2: 7.90DE; G3: 12.56CD; G4: 19.85BC; G5: 33.73A; G6: 20.77B; and for 1 year: G1: 2.43E; G2: 2.26E; G3: 4.3DE; G4: 18.79BC; G5: 26.49AB; G6: 22.73B.
  
  
  CONCLUSIONS
  Dentin deproteinization treatment with 10% NaOCI influenced the SBS compared with conventional treatment. The negative influence on SBS detected for conventional groups at 1-year interval was not detected for deproteinized groups.
  
  
  CONCLUSIONS
  The longevity of hybrid layer is critical due to the hydrolysis process at the adhesive interface over time. The use of 10% NaOCl deproteinization protocol might improve the longevity of bonding in adhesive restorations.
authors.affiliation: Department of Restorative Dentistry, Institute of Science and Technology, Universidade Estadual Paulista - UNESP São Paulo, Brazil.
authors.forename: César R
authors.initials: CR
authors.lastname: Pucci
authors.affiliation: Department of Restorative Dentistry, Institute of Science and Technology, Universidade Estadual Paulista - UNESP São Paulo, Brazil.
authors.forename: Natália R
authors.initials: NR
authors.lastname: Barbosa
authors.affiliation: Department of Restorative Dentistry, Institute of Science and Technology, Universidade Estadual Paulista - UNESP São Paulo, Brazil.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Bresciani
authors.affiliation: Department of Restorative Dentistry, Institute of Science and Technology, Universidade Estadual Paulista - UNESP São Paulo, Brazil.
authors.forename: Karen Ck
authors.initials: KC
authors.lastname: Yui
authors.affiliation: Department of Restorative Dentistry, Institute of Science and Technology, Universidade Estadual Paulista - UNESP São Paulo, Brazil.
authors.forename: Maria Filomena Rl
authors.initials: MF
authors.lastname: Huhtala
authors.affiliation: Department of Restorative Dentistry, São José dos Campos School of Dentistry, Universidade Estadual Paulista - UNESP São Paulo, Brazil.
authors.forename: Daphne C
authors.initials: DC
authors.lastname: Barcellos
authors.affiliation: Department of Restorative Dentistry, Institute of Science and Technology, Universidade Estadual Paulista - UNESP São Paulo, Brazil, Phone: +1239479048, e-mail: carlosrgt@fosjc.unesp.br.
authors.forename: Carlos Rg
authors.initials: CR
authors.lastname: Torres
mesh_terms: D000134:Acid Etching, Dental; D003094:Collagen / Q000187:drug effects*; D001840:Dental Bonding; D003804:Dentin / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D008963:Molar; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D012973:Sodium Hypochlorite / Q000494:pharmacology*
chemical_list: D017220:Dentin-Bonding Agents; D019279:Resin Cements; D003094:Collagen; D012973:Sodium Hypochlorite
keywords: Bond strength; Collagen; Degradation; Dentin; Matrix metalloproteinase Sodium hypochlorite.