title: Effect of drying methods on hybrid layer thickness.
abstract: OBJECTIVE
  To evaluate the effect of drying methods used in scanning electron microscopy on the thickness of the hybrid layers created by several different adhesive systems.
  
  
  METHODS
  A total etch dry bonding system, (Photobond), a three-step bonding adhesive system, (Scotchbond Multi-Purpose), a wet-bonding adhesive system (All-Bond 2) and a self-etching primer system (Mac Bond II) were used in this study. To permit measurement of the thickness of the hybrid layer, the resin-dentin interfaces were polished and etched briefly to remove polishing debris followed by immersion in 10% NaOCl for 4 hours. Half of the specimens in each group were subjected to fixation and critical-point drying followed by gold sputter-coating. The remaining specimens were allowed to air dry prior to gold sputter-coating. SEM observations were carried out to determine the structure and thickness of the hybrid layers.
  
  
  RESULTS
  The thickness of hybrid layers were affected by the drying methods with the critical-point drying methods producing the thickest hybrid layers (P < 0.05). The thickest hybrid layers were created by Photobond, with Scotchbond Multi-Purpose and All-Bond 2 producing intermediate thickness hybrid layers, among the total etch systems. The thinnest hybrid layer among all of the adhesive systems was produced by the self-etching primer, Mac Bond II.
authors.affiliation: Department of Operative Dentistry, Field of Biofunctional Recovery and Reconstruction, Okayama University Graduate School of Medicine and Dentistry, Japan.
authors.forename: Kousuke
authors.initials: K
authors.lastname: Itou
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Torii
authors.forename: Fumiko
authors.initials: F
authors.lastname: Oyama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yoshiyama
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
mesh_terms: D000134:Acid Etching, Dental; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D003890:Desiccation; D006801:Humans; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D016628:Replica Techniques; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D016707:Tissue Fixation / Q000379:methods
chemical_list: C112828:Clearfil AP-X; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C452442:Mac Bond II; D008689:Methacrylates; C481355:Photobond; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; C100742:All-Bond 2; D017438:Bisphenol A-Glycidyl Methacrylate