title: Effect of types of luting agent on push-out bond strength of zirconium oxide posts.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of different luting agents on the bond strength of zirconium oxide posts in root canals after artificial ageing.
  
  
  METHODS
  Thirty single-rooted extracted teeth were collected. Post spaces were prepared. Custom milled zirconium oxide posts (Cercon, Degudent) were fabricated. Specimens were divided into 3 groups (n=10), according to the luting agents used: group RA, conventional resin luting agent (RelyX ARC); group RU, self-adhesive resin luting agent (RelyX Unicem); and group Z, zinc phosphate luting agent (DeTrey). Specimens were subjected to thermocycling and water storage at 37°C. Specimens were horizontally sectioned into three sections and subjected to a push-out test with 0.5mm/min crosshead speed. The failure mode was assessed by scanning electron microscopy. Data were analysed by using 2-way ANOVA.
  
  
  RESULTS
  The following bond strength values were obtained: group RA - 8.89 MPa, group RU - 10.30 MPa and group Z - 9.31 MPa. There was no significant difference in bond strength among the groups (P=0.500). Adhesive failure mode at the cement/post bonded interface was seen in 100%, 66.67% and 83.3% of examined sections in groups RA, RU and Z, respectively. There was no significant difference in bond strength among different root regions (P=0.367).
  
  
  CONCLUSIONS
  The type of luting agent had no significant effect on the push-out bond strength of zirconium oxide posts after artificial ageing.
  
  
  CONCLUSIONS
  Conventional luting agents, such as zinc phosphate cement, seem to provide comparable retention to resin luting agents for cementing custom milled zirconium oxide posts.
authors: Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Drimplant_prostho@yahoo.com
authors: Khalil I
authors: KI
authors: Aleisa
authors: Balqees S
authors: BS
authors: Almufleh
authors: Steven M
authors: SM
authors: Morgano
authors: Christopher D
authors: CD
authors: Lynch
mesh_terms: D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate; D002484:Cementation / Q000379:methods; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents; D006801:Humans; D011092:Polyethylene Glycols; D011109:Polymethacrylic Acids; D011176:Post and Core Technique; D019279:Resin Cements; D012390:Root Canal Therapy; D033081:Shear Strength; D013718:Tensile Strength; D015036:Zinc Phosphate Cement; D015040:Zirconium
chemical_list: D003738:Dental Cements; D017220:Dentin-Bonding Agents; D011109:Polymethacrylic Acids; C483701:Rely X Unicem; C462240:RelyX ARC; D019279:Resin Cements; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D015036:Zinc Phosphate Cement; D015040:Zirconium; C028541:zirconium oxide