title: Marginal Vertical Discrepancies of Monolithic and Veneered Zirconia and Metal-Ceramic Three-Unit Posterior Fixed Dental Prostheses.
abstract: OBJECTIVE
  The aim of this study was to investigate and compare the marginal fit of posterior fixed dental prostheses (FDPs) made of monolithic and veneered computer-aided design/computer-assisted manufacture (CAD/CAM) zirconia ceramic with metal-ceramic posterior FDPs.
  
  
  METHODS
  Thirty standardized steel dies were prepared to receive posterior three-unit FDPs. Specimens were randomly divided into three groups (n = 10): (1) metal-ceramic (control group), (2) veneered zirconia, and (3) monolithic zirconia. All FDPs were cemented using a glass-ionomer cement. The specimens were subjected to thermal cycling (5°C to 55°C). A scanning electron microscope (SEM) with a magnification of ×500 was used for measurements. The data were statistically analyzed using one-way analysis of variance and paired t test.
  
  
  RESULTS
  Both zirconia groups showed similar vertical marginal discrepancies, and no significant differences (P = .661) in marginal adaptation were observed among the groups. No differences were observed in either group in marginal discrepancies between surfaces or abutments.
  
  
  CONCLUSIONS
  Monolithic zirconia posterior FDPs exhibit similar vertical marginal discrepancies to veneered zirconia posterior FDPs. No influence of localization measurements was observed.
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopez-Suarez
authors.forename: Esther
authors.initials: E
authors.lastname: Gonzalo
authors.forename: Jesus
authors.initials: J
authors.lastname: Pelaez
authors.forename: Benjamin
authors.initials: B
authors.lastname: Serrano
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Suarez
mesh_terms: D002484:Cementation / Q000379:methods; D002516:Ceramics / Q000737:chemistry*; D017076:Computer-Aided Design; D000044:Dental Abutments; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003801:Dental Veneers; D003779:Denture Design; D003830:Denture, Partial, Fixed; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D011897:Random Allocation; D013499:Surface Properties; D015019:Yttrium / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003764:Dental Materials; D005899:Glass Ionomer Cements; D016876:Metal Ceramic Alloys; C499362:yttria stabilized tetragonal zirconia; D015019:Yttrium; D015040:Zirconium; C028541:zirconium oxide