title: Effect of Storage Temperature on the Shelf Life of Self-adhesive Resin Cements.
abstract: OBJECTIVE
  To compare the bonding performance of three new self-adhesive resin cements to human dentin after storage under two different conditions.
  
  
  METHODS
  Buccal, lingual, mesial, and distal dentin surfaces of 36 human molars were abraded to directly below the enamel with #600 SiC papers. The teeth were divided into two main test groups. In the first test group (FT), the cements were kept in a refrigerator (6 ± 2°C) for three months and then used for the test. The remainder of the cements was kept at a constant room temperature of 19 ± 2°C for an additional three months, and then used again for the second test group (ST). Each test group comprised 6 teeth and 24 dentin sections. The cements Clearfil SA (CSA), G-Cem (GC), and Bis-Cem (BC) were applied to the surfaces according to the manufacturers' recommendations. After application of the cements to the flat dentin surfaces and light curing, shear bond strengths were determined at a crosshead speed of 0.5 mm/min. Bond strengths were then calculated and expressed in MPa. Data were analyzed with Kruskal-Wallis and Wilcoxon Signed Rank tests. To investigate the cement/ dentin interfaces using SEM, the buccal surfaces of three additional teeth were used for each test group.
  
  
  RESULTS
  The bond strength values of cement groups were significantly different for the FT and ST groups (p < 0.01). GC showed the highest bond strength values of all materials. There was a difference between the bond strength values of the two testing periods for all materials (p < 0.01). Bond strengths significantly decreased after storage at room temperature.
  
  
  CONCLUSIONS
  Storage temperatures considerably affect the shelf life of self-adhesive resin cements.
authors.forename: Fusun
authors.initials: F
authors.lastname: Ozer
authors.forename: Hesna Sazak
authors.initials: HS
authors.lastname: Ovecoglu
authors.forename: Leila
authors.initials: L
authors.lastname: Daneshmehr
authors.forename: Gulden
authors.initials: G
authors.lastname: Sinmazisik
authors.forename: Kanupriya
authors.initials: K
authors.lastname: Kashyap
authors.forename: Emre
authors.initials: E
authors.lastname: Iriboz
authors.forename: Markus B
authors.initials: MB
authors.lastname: Blatz
mesh_terms: D003080:Cold Temperature; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure; D004355:Drug Stability; D004356:Drug Storage; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: C542562:BisCem cement; C581302:Clearfil SA; D003188:Composite Resins; C528107:G-Cem resin cement; D019279:Resin Cements