title: Metal surface treatment: characterization and effect on composite-to-metal bond strength.
abstract: This study evaluated the effect of four methods of metal surface preparation and the use of silane on the bond strength between resin and a Noble metal alloy. SEM Examination and x-ray energy-dispersive spectroscopy (EDS) of the various metal surface treatments was also performed. One-hundred metal disks were cast in a Noble metal alloy (Porcelain #76). Ninety disks were polished flat and the surfaces received one of four abrasive treatments (n = 20). 1) Roughening with a diamond bur at high speed; 2) Air abrasion with an intraoral sandblaster using alumina particles; 3) Air abrasion with KCP-2000 and 4) Air abrasion with an intraoral sandblaster using silanated silica covered alumina particles (CoJet-Sand). Half the specimens from each treatment group (n = 10) were silanated prior to bonding procedures (All-Bond 2 adhesive system, Pertac-Hybrid composite). Specimens were stored in distilled water at 37 degrees C and thermocycled prior to shear strength testing. The 10 remaining metal disks were used for scanning electron microscopy and x-ray energy-dispersive spectroscopy (EDS). Scanning electron microscopy examined the micromorphology of the metal surfaces produced by the four abrasive treatments and x-ray energy-dispersive spectroscopy (EDS) to evaluate changes in surface composition. Two untreated disks served as controls. One-way ANOVA and Tukey's HSD post-hoc test demonstrated that air abrasion with CoJet-Sand and silane resulted in significantly higher resin-to-metal bond strength than all other metal surface treatments, while roughening with a diamond bur produced the lowest bond strength. Resin-to-metal bond strength was similar for all other particle abrasive treatments with or without silane. Using silane significantly improved bond strength only for metal surfaces treated with CoJet-Sand. An increase in Al concentration was observed on metal surfaces sandblasted with aluminum oxide, and an increase in the concentration of both Al and Si was observed on surfaces air-abraded with CoJet-Sand.
authors.affiliation: Department of Operative Dentistry, College of Dentistry, The University of Iowa, Iowa City, Iowa 52242, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Cobb
authors.forename: M A
authors.initials: MA
authors.lastname: Vargas
authors.forename: T A
authors.initials: TA
authors.lastname: Fridrich
authors.forename: M R
authors.initials: MR
authors.lastname: Bouschlicher
mesh_terms: D000388:Air; D000535:Aluminum / Q000032:analysis; D000537:Aluminum Oxide / Q000737:chemistry; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003722:Dental Alloys / Q000032:analysis / Q000737:chemistry*; D001840:Dental Bonding; D003754:Dental High-Speed Equipment; D018130:Diamond; D004577:Electron Probe Microanalysis; D006801:Humans; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000032:analysis / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000032:analysis / Q000737:chemistry; D013223:Statistics as Topic; D013314:Stress, Mechanical; D013499:Surface Properties; D013816:Thermodynamics; D014867:Water
chemical_list: D003188:Composite Resins; D003722:Dental Alloys; D016876:Metal Ceramic Alloys; D008689:Methacrylates; C079764:Pertac hybrid; D012821:Silanes; D014867:Water; C100742:All-Bond 2; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D018130:Diamond; D000535:Aluminum; D000537:Aluminum Oxide