title: Comparison of chemical aging and water immersion time on durability of resin-dentin interface produced by an etch-and-rinse adhesive.
abstract: OBJECTIVE
  The aim of this study was to analyze and compare the influence of short-term NaOCl-storage and long-term water storage on the microtensile bond strength (µTBS) of etch-and-rinse adhesive system to human dentin.
  
  
  METHODS
  Thirty-six third human molars were randomly divided into 6 groups (n = 6) according to the aging protocol: G1 (water, 24 hours); G2 (water, 6 months); G3 (water, 12 months); G4 (10% sodium hypochlorite--NaOCl, 1 hour); G5 (10% NaOCl, 3 hours) and G6 (10% NaOCl, 5 hours). A two-step etch-and-rinse adhesive (Adper Single Bond 2) was applied according to the manufacturers' instructions. A composite (Filtek Z250) was applied in four horizontal increments and was individually cured. Specimens were cut following the microtensile test technique, submitted to the different aging protocols, and tested in tension. The fracture pattern was observed in a stereomicroscope (40* magnification) and in a scanning electron microscope. The µTBS data were analyzed by ANOVA and Tukey's test (α = 0.05).
  
  
  RESULTS
  The effect of storage in 10% NaOCl for 1 or 3 hours was not significantly different from that of aging in distilled water (DW) for 6 or 12 months (p > 0.05). Beams immersed in DW for 24 hours and in 10% NaOCl for 5 hours showed the highest and lowest µTBS values respectively.
  
  
  CONCLUSIONS
  The aging protocols negatively influenced dentin bond strength. Aging specimens in 10% NaOCl for 1 or 3 hours can be an alternative method for long-term water storage (6 or 12 months) bond strength studies.
  
  
  CONCLUSIONS
  This aging protocol allows a quick achievement of longitudinal bond strength data, so that results are available to the professionals in this area while the materials are yet present at the dental market.
authors.affiliation: Department of Operative Dentistry, School of Dentistry, University of Sao Paulo, Brazil.
authors.forename: Bruna Uglik
authors.initials: BU
authors.lastname: Garbui
authors.forename: Sergio Brossi
authors.initials: SB
authors.lastname: Botta
authors.forename: Andre Figueiredo
authors.initials: AF
authors.lastname: Reis
authors.forename: Adriana Bona
authors.initials: AB
authors.lastname: Matos
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins; D001840:Dental Bonding; D003738:Dental Cements; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D004356:Drug Storage; D006801:Humans; D007101:Immersion; D019279:Resin Cements / Q000737:chemistry*; D012973:Sodium Hypochlorite; D018709:Statistics, Nonparametric; D013718:Tensile Strength; D013997:Time Factors; D014867:Water
chemical_list: C554641:Adper single bond 2; D003188:Composite Resins; D003738:Dental Cements; D017220:Dentin-Bonding Agents; C444701:Filtek Z250; D019279:Resin Cements; D014867:Water; D012973:Sodium Hypochlorite