title: Effect of different surface treatments on adhesion of In-Ceram Zirconia to enamel and dentin substrates.
abstract: OBJECTIVE
  Resin bonding of In-Ceram Zirconia (ICZ) ceramics is still a challenge, especially for minimally invasive applications. This study evaluated the adhesion of ICZ to enamel and dentin after different surface treatments of the ceramic.
  
  
  METHODS
  ICZ ceramic specimens (diameter: 6 mm; thickness: 2 mm) (N = 100) were fabricated following the manufacturer's instructions and randomly assigned to 5 groups (n = 20), according to the surface treatment methods applied. The groups were as follows: group C: no treatment; group SB: sandblasting; group SCS-S: CoJet+silane; group SCS-P: CoJet+Alloy Primer; group GE-S: glaze+ hydrofluoric acid etching (9.6%) for 60 s+silane. Each group was randomly divided into two subgroups to be bonded to either enamel or dentin (n = 10 per group) using MDP-based resin cement (Panavia F2.0). All the specimens were subjected to thermocycling (5000x, 5°C-55°C). The specimens were mounted in a universal testing machine and tensile force was applied to the ceramic/cement interface until failure occurred (1 mm/min). After evaluating all the debonded specimens under SEM, the failure types were defined as either "adhesive" with no cement left on the ceramic surface (score 0) or "mixed" with less than 1/2 of the cement left adhered to the surface with no cohesive failure of the substrate (score 1). The data were statistically evaluated using 2-way ANOVA and Tukey's tests (α = 0.05).
  
  
  RESULTS
  The highest tensile bond strength for the enamel surfaces was obtained in group GE-S (18.1 ± 2 MPa) and the lowest in group SB (7.1 ± 1.4 MPa). Regarding dentin, group CSC-P showed the highest (12 ± 1.3 MPa) and SB the lowest tensile bond strength (5.7 ± 0.4 MPa). Groups SB, CSC-S, CSC-P, and GE-S did not show significant differences between the different surface treatments on either enamel or dentin surfaces (p < 0.05, p < 0.001, respectively). Groups CSC-P and GE-S presented similar bond strength for both the enamel and dentin substrates (p < 0.8 and p < 0.9), respectively. While on enamel substrates, exclusively adhesive failures from ICZ (score 0) were found, on dentin exclusively mixed failures were observed (score 1).
  
  
  CONCLUSIONS
  Adhesion of ICZ to both enamel and dentin can be improved when ceramics are glazed, etched, and silanized, or sandblasted, primed, and cemented with an MDP-based cement.
authors.affiliation: Mansoura University, Egypt. mutluozcan@hotmail.com
authors.forename: Samah
authors.initials: S
authors.lastname: Saker
authors.forename: Fatma
authors.initials: F
authors.lastname: Ibrahim
authors.forename: Mutlu
authors.initials: M
authors.lastname: Ozcan
mesh_terms: D000134:Acid Etching, Dental; D020906:Air Abrasion, Dental; D001840:Dental Bonding; D003743:Dental Enamel; D003776:Dental Porcelain; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin; D006801:Humans; D008963:Molar; D019279:Resin Cements; D013499:Surface Properties; D013718:Tensile Strength; D019246:Tooth Preparation / Q000379:methods*
chemical_list: C485633:In-Ceram Zirconia; C438843:Panavia-Fluoro; D019279:Resin Cements; D003776:Dental Porcelain