title: Effect of different laser surface treatment on microshear bond strength between zirconia ceramic and resin cement.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of sandblasting, carbon dioxide (CO₂), and erbium,chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers on the microshear bond strength of zirconia to resin cement.
  
  
  METHODS
  Sixty-one sintered yttria stabilized tetragonal zirconia blocks (10 × 5 × 2 mm) were prepared and divided into four experimental groups (n = 15); one sample was retained as a control. The samples were treated by aluminium oxide air abrasion, CO₂4W, Er,Cr:YSGG 3W, and Er,Cr:YSGG 2W, respectively. One sample from each group and the control sample were analyzed by scanning electron microscope. Panavia F2.0 resin microcylinders were prepared and placed on treated surfaces, light cured, and incubated for 48 h. Microshear bond strength testing was done by a microtensile tester machine, and the type of bond failures were determined by stereomicroscope. Data were analyzed by one-way anova and Tukey's test at a significance level of P < 0.05.
  
  
  RESULTS
  Air abrasion showed the highest microshear bond strength (P < 0.05) among all groups. CO₂and Er,Cr:YSGG 3W laser showed significantly higher bond strength than Er,Cr:YSGG 2W (P < 0.05). Apparent micromechanical roughening and irregularities were seen in the air abrasion-treated samples, and the bond failure was mostly mixed type. In the laser-treated surfaces, the roughness was much less than the air abrasion-treated surfaces, and the mode of failure was almost pure adhesive.
  
  
  CONCLUSIONS
  Air abrasion has a greater effect than CO₂and Er,Cr:YSGG lasers in the treatment of zirconia ceramic surfaces to enhance the bonding strength of resin cement to zirconia. CO₂laser at 4W and Er,Cr:YSGG laser at only 3-W output power can be regarded as surface treatment options for roughening the zirconia surface to establish better bond strength with resin cements.
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Vagharaldin
authors.initials: V
authors.lastname: Akhavan Zanjani
authors.affiliation: School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hadi
authors.initials: H
authors.lastname: Ahmadi
authors.affiliation: School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Afshin
authors.initials: A
authors.lastname: Nateghifard
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Ghasemi
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Torabzadeh
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Abdoh Tabrizi
authors.affiliation: School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Farnaz
authors.initials: F
authors.lastname: Alikhani
authors.affiliation: School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Razi
authors.affiliation: Department of Biological Sciences, San Jose State University, San Jose, CA, USA.
authors.forename: Ardalan
authors.initials: A
authors.lastname: Nateghifard
mesh_terms: D000268:Adhesiveness; D000537:Aluminum Oxide / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D001840:Dental Bonding; D045662:Dental Etching / Q000295:instrumentation / Q000379:methods*; D003764:Dental Materials / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D006801:Humans; D006813:Humidity; D007834:Lasers; D054020:Lasers, Gas; D053844:Lasers, Solid-State; D055115:Light-Curing of Dental Adhesives / Q000379:methods; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning / Q000379:methods; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003764:Dental Materials; C438843:Panavia-Fluoro; D019279:Resin Cements; C499362:yttria stabilized tetragonal zirconia; D015019:Yttrium; D015040:Zirconium; D000537:Aluminum Oxide
keywords: bond strength; dentistry; laser; resin cement; zirconia ceramic