title: Analysis of Vertical Marginal Adaptation of Zirconia Fixed Dental Prosthesis Frameworks Fabricated by the CAD/CAM System: A Randomized, Double-Blind Study.
abstract: The purpose of this study was to evaluate the marginal adaptation of fixed dental prosthesis frameworks fabricated by computer-aided design/computer-assisted manufacture (CAD/CAM) with three different systems of data acquisition.
  
  
  
  A total of 50 specimens were fabricated as follows: using the conventional method (Ni-Cr) (n=10); iTero/industrial milling (Group 1, n=10); Cerec Bluecam/industrial milling (Group 2, n=10); 3S/industrial milling (Group 3, n=10); and Cerec BlueCam/Sirona milling (Group 4, n=10). The specimens were numbered and randomized, and the vertical marginal discrepancy was analyzed.
  
  
  
  Intraobserver analysis indicated no statistically significant difference (paired t test, P=.822) between periods before and after analysis. The conventional method (321 μm) showed greater discrepancy when compared with the CAD/CAM system (89 μm) (P<.001). The intraoral system showed a lower rate of marginal discrepancy when compared with the extraoral system (3S) (P<.001). The closed system presented a higher marginal discrepancy (114 μm) than the open intraoral system (iTero) at P<.001. In addition, the intraoral system when open showed statistically significant differences in mean marginal discrepancy values compared with the same system in closed condition (P>.05).
  
  
  
  The CAD/CAM systems showed less marginal discrepancy than the conventional method for the fabrication of the frameworks.
authors.forename: Caroline
authors.initials: C
authors.lastname: Mello
authors.forename: Joel Ferraro
authors.initials: JF
authors.lastname: Santiago Junior
authors.forename: Graziela
authors.initials: G
authors.lastname: Galhano
authors.forename: Jose Vitor
authors.initials: JV
authors.lastname: Quinelli Mazaro
authors.forename: Roberto
authors.initials: R
authors.lastname: Scotti
authors.forename: Eduardo
authors.initials: E
authors.lastname: Pellizzer
mesh_terms: D002858:Chromium Alloys / Q000737:chemistry; D017076:Computer-Aided Design; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003779:Denture Design / Q000706:statistics & numerical data; D003830:Denture, Partial, Fixed / Q000706:statistics & numerical data; D006801:Humans; D008422:Materials Testing; D013499:Surface Properties; D015040:Zirconium / Q000737:chemistry*
chemical_list: D002858:Chromium Alloys; D003764:Dental Materials; D015040:Zirconium; C028541:zirconium oxide