title: The Effect of Artificial Aging on The Bond Strength of Heat-activated Acrylic Resin to Surface-treated Nickel-chromium-beryllium Alloy.
abstract: OBJECTIVE
  The debonding load of heat-activated polymethylmethacrylate (PMMA) denture base resin material to a nickel-chromium-beryllium (Ni-Cr-Be) alloy conditioned by three different surface treatments and utilizing two different commercial bonding systems was investigated.
  
  
  METHODS
  Denture resin (Lucitone-199) was bonded to Ni-Cr-Be alloy specimens treated with Metal Primer II, the Rocatec system with opaquer and the Rocatec system without opaquer. Denture base resin specimens bonded to non-treated sandblasted Ni-Cr-Be alloy were used as controls. Twenty samples for each treatment condition (80 specimens) were tested. The 80 specimens were divided into two categories, thermocycled and non-thermocycled, containing four groups of ten specimens each. The non-thermocycled specimens were tested after 48 hours' storage in room temperature water. The thermocycled specimens were tested after 2,000 cycles in 4°C and 55°C water baths. The debonding load was calculated in Newtons (N), and collected data were subjected by non parametric test Kruskal-Wallis One Way Analysis of Variance on Ranks and Dunn's post hoc test at the α = 0.05.
  
  
  RESULTS
  The Metal Primer II and Rocatec system without opaquer groups produced significantly higher bond strengths (119.9 and 67.6 N), respectively, than did the sandblasted and Rocatec system with opaquer groups, where the bond strengths were 2.6 N and 0 N, respectively. The Metal Primer II was significantly different from all other groups (P<0.05). The bond strengths of all groups were significantly decreased (P<0.05) after thermocycling.
  
  
  CONCLUSIONS
  Although thermocycling had a detrimental effect on the debonding load of all surface treatments tested, the Metal Primer II system provided higher values among all bonding systems tested, before and after thermocycling.
authors.affiliation: Dental Biomaterials Research and Development Chair, College of Dentistry, King Saud University, Riyadh - Saudi Arabia.
authors.forename: Youssef S
authors.initials: YS
authors.lastname: Al Jabbari
authors.affiliation: Department of Biomaterials, School of Dentistry, Athens University, Athens, Greece; Consultant, Dental Biomaterials Research and Development Chair, College of Dentistry, King Saud University, Riyadh - Saudi Arabia.
authors.forename: Spiros
authors.initials: S
authors.lastname: Zinelis
authors.affiliation: Dental Biomaterials Research and Development Chair, College of Dentistry, King Saud University, Riyadh - Saudi Arabia.
authors.forename: Sara M
authors.initials: SM
authors.lastname: Al Taweel
authors.affiliation: Graduate Prosthodontics, Baylor College of Dentistry, Texas A&M University, Dallas, Texas - USA.
authors.forename: William W
authors.initials: WW
authors.lastname: Nagy
keywords: Debonding load; Denture base material; Metal conditioners; Nickel-chromium-beryllium alloy; Rocatec system