title: Aging affects the adhesive interface of posts luted with self-adhesive cements: a 1-year study.
abstract: OBJECTIVE
  To examine the bond strength and interfacial nanoleakage expression of fiber posts luted to intraradicular dentin with self-adhesive cements. Six-month and 1-year aging effects were examined.
  
  
  METHODS
  Post space was created in endodontically treated human incisors. Each tooth was assigned to a self-adhesive cement/post combination: (1) Bifix SE Cement (Voco) with proprietary posts (Rebilda Post, Voco), (2) RelyX Unicem (3M ESPE) with proprietary posts (Rely X Fiber Post, 3M ESPE), (3) MaxCem (Kerr) with Rebilda Posts. Each specimen was cut into 1-mm-thick sections and either immediately stressed to failure with the push-out bond strength test or aged in artificial saliva for 6 months or 1 year before testing. Additional specimens were processed for quantitative interfacial nanoleakage analysis using ammoniacal silver nitrate.
  
  
  RESULTS
  Immediate bond strength ranked in the following order: Bifix SE (7.8 ± 2.9 MPa) = RelyX Unicem (8.4 ± 2.7 MPa) > MaxCem (4.6 ± 2.4 MPa) (p < 0.05). Aging significantly reduced the bond strength of all cements after 1 year: Bifix SE (3.8 ± 1.4 MPa) = RelyX Unicem (5.8 ± 1.7 MPa) > MaxCem (1.3 ± 0.9 MPa; p<0.05). No immediate difference in interfacial nanoleakage expression was found. Nanoleakage increased after aging, and MaxCem showed the highest values.
  
  
  CONCLUSIONS
  The push-out strength and interfacial nanoleakage expression of fiber posts luted with self-adhesive cements were dependent on luting material and type of post, and were significantly affected by storage time.
authors.affiliation: Department of Medical Sciences, University of Trieste, Trieste, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Marchesi
authors.forename: Annalisa
authors.initials: A
authors.lastname: Mazzoni
authors.forename: Gianluca
authors.initials: G
authors.lastname: Turco
authors.forename: Milena
authors.initials: M
authors.lastname: Cadenaro
authors.forename: Marco
authors.initials: M
authors.lastname: Ferrari
authors.forename: Roberto
authors.initials: R
authors.lastname: Di Lenarda
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
mesh_terms: D003188:Composite Resins; D001840:Dental Bonding; D003763:Dental Leakage; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004356:Drug Storage; D006801:Humans; D007180:Incisor; D011176:Post and Core Technique; D019279:Resin Cements / Q000737:chemistry; D013997:Time Factors
chemical_list: C515607:Bifix composite; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C515955:Maxcem; C483701:Rely X Unicem; D019279:Resin Cements