title: New zirconia primer improves bond strength of resin-based cements.
abstract: OBJECTIVE
  Various chemical interactions can be used to develop ceramic-resin bonding and specific approaches are available for zirconia ceramics. This study evaluated the effect of a new experimental primer, a mixture of organophosphate and carboxylic acid monomers, on the zirconia-to-resin shear bond strength (SBS).
  
  
  METHODS
  Forty Y-TZP blocks (15x4x2mm) were embedded in an acrylic resin base, polished, Al(2)O(3)-sandblasted and randomly divided into eight groups. Three different resin-based luting agents (BisCem, Duo-Link, Panavia F) were used to build 2.4mm-diameter cylinders (n=15) onto the zirconia surface with and without the new experimental zirconia primer. The new primer was also tested with Z100 restorative composite resin cylinders. In addition, Panavia was used with its own primer (Clearfil Ceramic Primer). SBS testing was carried out after 24h of storage in water. Scanning electron microscopy (SEM) was used to evaluate the zirconia surface topography and failure mode.
  
  
  RESULTS
  According to ANOVA and Tukey test (alpha=0.05), the association of the experimental primer with the restorative composite resin Z100 yielded the highest SBS (29.35MPa) followed by DuoLink with the new primer (26.68MPa). The groups that did not receive the experimental primer presented the lowest SBS values (from 5.95 to 9.79MPa). The failure mode was adhesive for the non-primed specimens and predominantly mixed in the primed groups.
  
  
  CONCLUSIONS
  The use of the new zirconia experimental primer based on organophosphate/carboxylic acid monomers increased the bond strength of different resin-based luting agents including Z100 restorative material.
authors.affiliation: Division of Restorative Sciences, School of Dentistry, Oral Health Center, University of Southern California, 3151 Hoover Street, Los Angeles, CA 90089, USA. magne@usc.edu
authors.forename: Pascal
authors.initials: P
authors.lastname: Magne
authors.forename: Maria P G
authors.initials: MP
authors.lastname: Paranhos
authors.forename: Luiz H
authors.initials: LH
authors.lastname: Burnett
mesh_terms: D020906:Air Abrasion, Dental; D000704:Analysis of Variance; D002264:Carboxylic Acids / Q000737:chemistry; D003188:Composite Resins; D001840:Dental Bonding; D003776:Dental Porcelain; D003799:Dental Stress Analysis; D008422:Materials Testing; D010755:Organophosphates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013499:Surface Properties; D015019:Yttrium; D015040:Zirconium
chemical_list: D002264:Carboxylic Acids; D003188:Composite Resins; D010755:Organophosphates; D019279:Resin Cements; C499362:yttria stabilized tetragonal zirconia; D003776:Dental Porcelain; D015019:Yttrium; D015040:Zirconium