title: Effect of gold sputtering on the adhesion of porcelain to cast and machined titanium.
abstract: BACKGROUND
  The bond strength of porcelain to titanium is insufficient to provide a clinically acceptable alternative to existing alloys for metal ceramic restorations.
  
  
  OBJECTIVE
  The purpose of the study was to investigate the effect of gold coating on the adhesion of porcelain to titanium.
  
  
  METHODS
  Forty titanium plates (25 × 8 × 1 mm) were prepared by casting and machining procedures to make 2 groups of each type (n=10). All plates were subjected to airborne-particle abrasion with alumina powder. One of each of the cast and machined groups was gold sputtered. A layer of porcelain was built up onto the titanium plates of all groups with a conventional technique. A precrack was created at the center of the specimen. Specimens were then subjected to a 4-point bending test with a universal testing machine. The load recorded from the test was used to determine adhesion in terms of the strain energy release rate (G value). The data were analyzed with ANOVA and post hoc testing (α=.05). The interfacial area of the tested specimen was then examined with scanning electron microscopy.
  
  
  RESULTS
  The G values of the gold-sputtered groups were significantly higher than those of the uncoated groups for both cast and machined groups (P<.05). No significant differences were noted within the groups.
  
  
  CONCLUSIONS
  The adhesion between porcelain and titanium was significantly improved when titanium was sputter coated with gold in both the cast and machined groups.
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Rathanak
authors.initials: R
authors.lastname: Khung
authors.forename: Napa Sukjai
authors.initials: NS
authors.lastname: Suansuwan
mesh_terms: D000465:Algorithms; D000537:Aluminum Oxide / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D001840:Dental Bonding; D003734:Dental Casting Investment / Q000737:chemistry; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing; D003776:Dental Porcelain / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D006046:Gold / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D018583:Pliability; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D003734:Dental Casting Investment; D003764:Dental Materials; D016876:Metal Ceramic Alloys; D003776:Dental Porcelain; D006046:Gold; D014025:Titanium; D000537:Aluminum Oxide