title: Effect of surface treatments on the bonding strength of self-adhesive resin cements to zirconia ceramics.
abstract: OBJECTIVE
  To investigate the effect of surface treatments on the surface properties of yttria-stabilized zirconia ceramics (Y-TZP) and the interfacial bond strength to self-adhesive resin cements.
  
  
  METHODS
  Two types of Y-TZP (Vita In-Ceram YZ [VZ] and IPS e.max ZirCAD [IZ]) were used. The specimens were divided into four groups in each test according to the surface treatment used: Group A (control; no treatment), Group B (airborne-particle abrasion), Group C (CH₂Cl₂ for 60 minutes), and Group D (hot etching for 60 minutes). Scanning electron microscopy, atomic force microscopy, and X-ray diffractometry were carried out. Two types of self-adhesive resin cements (i CEM [IC] and Multilink Speed [MS]) were used for testing the adhesion. The G-value (J/m²) was measured with a four-point bending configuration. Following fracture testing, specimens were examined with a stereomicroscope. Data were analyzed using ANOVA and Tukey test.
  
  
  RESULTS
  IZ treated with hot etching showed the highest average surface roughness values (172.5 ± 15.43 nm) compared with the other groups (P < .05). The greatest amount of monoclinic phase was measured after airborne-particle abrasion for VZ (8.9%), followed by IZ (6.1%). Improvements in bond strength values were found in the following order: hot etching > CH2Cl2 > airborne-particle abrasion > no treatment. Most failure modes were adhesive type of failures between ceramics and cement material (68.76%).
  
  
  CONCLUSIONS
  Adhesion between Y-TZP and self-adhesive resin cements can be improved by the use of CH₂Cl₂ or hot etching surface treatments prior to resin cement application as an alternative technique to airborne-particle abrasion treatment.
authors.affiliation: Department of Dental Biomaterials, Faculty of Dentistry, Mansoura University, Egypt. shaymanaghy@mans.edu.eg
authors.forename: Shaymaa E
authors.initials: SE
authors.lastname: Elsaka
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000268:Adhesiveness; D000537:Aluminum Oxide / Q000737:chemistry; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D006358:Hot Temperature; D008422:Materials Testing; D008752:Methylene Chloride / Q000737:chemistry; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D018583:Pliability; D019279:Resin Cements / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014961:X-Ray Diffraction; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003764:Dental Materials; C520133:IPS e.max CAD LT; C485633:In-Ceram Zirconia; D019279:Resin Cements; D012997:Solvents; C502351:multilink adhesive system; C499362:yttria stabilized tetragonal zirconia; D003776:Dental Porcelain; D015019:Yttrium; D008752:Methylene Chloride; D015040:Zirconium; D000537:Aluminum Oxide