title: Comparison of resin bonding improvements to zirconia between one-bottle universal adhesives and tribochemical silica coating, which is better?
abstract: OBJECTIVE
  To evaluate the bonding of resin-cement to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) via silica coating followed by silanization, and three one-bottle universal adhesives, with or without prior conditioning using a zirconia primer.
  
  
  METHODS
  Y-TZP specimens (n=160) were conditioned by tribochemical silica coating and silanization (CS), or alumina sandblasting with one of the following MDP containing adhesives or primers: Z-Prime Plus™ (zirconia primer, ZP), Single Bond Universal™ (SU), Clearfil Universal Bond™ (CU) or All-Bond Universal™ (AU). Additionally, some specimens (ZPSU, ZPCU and ZPAU) received Z-Prime Plus™ followed by one of the three adhesives. After 24h water storage and "aging" (20,000 thermocycles plus additional 40-day water storage), shear bond strength (SBS) was measured. Fourier-transform infrared spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) were employed for characterization of the chemical bonds between the primer/adhesives and the zirconia. Thermodynamic calculations were used to examine the hydrolytic stability between the MDP-zirconia chemical bonds and the SiO2-silane chemical bonds.
  
  
  RESULTS
  The CS and ZPCU groups showed higher SBS than the other six groups. There were no significant pairwise differences amongst ZP, SU and ZPSU, or amongst ZP, AU and ZPAU. Aging led to significantly decreased SBS for all groups except CS and ZPCU. There was no statistically significant interaction between surface treatment and aging. XPS determined the chemical bonds between MDP and zirconia. FTIR showed similar shifts in characteristic phosphate peaks for all the primer and/or adhesive groups. Result of thermodynamic calculation showed that equilibrium constant of SiO2-silane system is much larger than the one of MDP-tetragonal phase zirconia system.
  
  
  CONCLUSIONS
  The application of one-bottle universal adhesives after alumina sandblasting is an alternative to tribochemical silica coating with silanization for bonding to zirconia, while bonding between resin and Y-TZP is more susceptible to hydrolysis when zirconia primer or one-bottle universal adhesive is used.
authors.affiliation: Jiangsu Key Laboratory of Oral Diseases, Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Xie
authors.affiliation: Jiangsu Key Laboratory of Oral Diseases, Department of Endodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory of Oral Diseases, Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China.
authors.forename: Feimin
authors.initials: F
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department of Endodontics, College of Dental Medicine, Georgia Regents University, Augusta, GA, USA.
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
authors.affiliation: Jiangsu Key Laboratory of Oral Diseases, Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China.
authors.forename: Mengke
authors.initials: M
authors.lastname: Qian
authors.affiliation: Jiangsu Key Laboratory of Oral Diseases, Department of Endodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China. Electronic address: ccchicy@njmu.edu.cn.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D019279:Resin Cements / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: C074864:All-Bond system; C029849:Clearfil Bonding Agent; D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D019279:Resin Cements; D012821:Silanes; C000613955:Z-Prime Plus; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate; D015019:Yttrium; D012822:Silicon Dioxide; D015040:Zirconium; C028541:zirconium oxide; C091417:yttria
keywords: Adhesion; Bond; Dental zirconia; MDP; Phosphate ester; Primer; Universal adhesives; Y-TZP