title: Bonding of resin cement to zirconia with high pressure primer coating.
abstract: OBJECTIVE
  To investigate the effect of air-drying pressure during ceramic primer coating on zirconia/resin bonding and the surface characteristics of the primed zirconia.
  
  
  METHODS
  Two ceramic primers (Clearfil Ceramic Primer, CCP, Kuraray Medical Inc. and Z-Prime Plus, ZPP, Bisco Inc.) were applied on the surface of air-abraded zirconia (Katana zirconia, Noritake) and dried at 4 different air pressures (0.1-0.4 MPa). The primed zirconia ceramic specimens were bonded with a resin-based luting agent (SA Luting Cement, Kuraray). Micro-shear bond strengths of the bonded specimens were tested after 3 days of water storage or 5,000× thermocycling (n = 12). Failure modes of the fractured specimens were examined with scanning electron miscopy. The effects of air pressure on the thickness of the primer layers and the surface roughness (Sa) of primed zirconia were evaluated using spectroscopic ellipsometry (n = 6), optical profilometry and environmental scanning electron microscopy (ESEM) (n = 6), respectively.
  
  
  RESULTS
  Clearfil Ceramic Primer air-dried at 0.3 and 0.4 MPa, yielding significantly higher µSBS than gentle air-drying subgroups (p < 0.05). Compared to vigorous drying conditions, Z-Prime Plus air-dried at 0.2 MPa exhibited significantly higher µSBS (p < 0.05). Increasing air-drying pressure reduced the film thickness for both primers. Profilometry measurements and ESEM showed rougher surfaces in the high pressure subgroups of CCP and intermediate pressure subgroup of ZPP.
  
  
  CONCLUSIONS
  Air-drying pressure influences resin/zirconia bond strength and durability significantly. Higher air-drying pressure (0.3-0.4 MPa) for CCP and intermediate pressure (0.2 MPa) for ZPP are recommended to produce strong, durable bonds between resin cement and zirconia ceramics.
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Li-na
authors.initials: LN
authors.lastname: Niu
authors.affiliation: State Key Laboratory of Military Stomatology, Department of General and Emergency, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Ying-jie
authors.initials: YJ
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Kai
authors.initials: K
authors.lastname: Jiao
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Li-juan
authors.initials: LJ
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Ming
authors.initials: M
authors.lastname: Fang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Endodontics, College of Dental Medicine, Georgia Regents University, Augusta, Georgia, United States of America.
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.
authors.forename: Ji-hua
authors.initials: JH
authors.lastname: Chen
mesh_terms: D008422:Materials Testing; D011312:Pressure; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013499:Surface Properties; D013718:Tensile Strength; D015040:Zirconium / Q000737:chemistry*
chemical_list: D019279:Resin Cements; D015040:Zirconium; C028541:zirconium oxide