title: [The durability of three self-etch adhesives bonded to dentin].
abstract: OBJECTIVE
  To investigate the durability of self-etch adhesives bonded to dentin in vitro.
  
  
  METHODS
  Forty-two extracted human molars were selected and occlusal dentin surfaces were exposed. The teeth were randomly distributed into three groups based on adhesives applied. The one-step self-etch adhesive B(Adper Prompt) and C(G-Bond) and two-step self-etch adhesive A (Clearfil SE bond) were used. After application of the adhesives to the dentin surfaces, composite crowns were built up, after 24 h water storage, the teeth were sectioned longitudinally into sticks (1.0 mm×1.0 mm bonding area) for microtensile testing or slabs (1 mm thick) for scanning electron microscopec (SEM) observation. Bonding strength (mTBS) and nano-leakage were evaluated immediately after cutting or after 6 months in water. The mTBS was analyzed using one-way ANOVA (SPSS 13.0). The nanoleakage was observed by SEM with a backscattered electron detector.
  
  
  RESULTS
  Both adhesives and water storage time affected the mTBS. All adhesives showed decreased bond strength after six-month water aging [A dropped from (40.60 ± 5.76) MPa to (36.04 ± 3.15) MPa; B dropped from (19.06 ± 1.50) MPa to (11.19 ± 1.97) MPa; C dropped from (17.75 ± 1.10) MPa to (9.14 ± 1.15) MPa] (P < 0.05). B and C showed lower mTBS than A after aging (P < 0.05). Compared to A, nanoleakage was more obvious after aging for B and C.
  
  
  CONCLUSIONS
  All self-etch adhesives tested were probably influenced by water aging, however, the two-step adhesive showed better durability than the one-step adhesives.
authors.affiliation: Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Fu-Cong
authors.initials: FC
authors.lastname: Tian
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Wang
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Gao
mesh_terms: D000269:Adhesives; D001840:Dental Bonding; D003804:Dentin; D006801:Humans; D008422:Materials Testing; D013718:Tensile Strength
chemical_list: D000269:Adhesives