title: Ceramic materials for porcelain veneers: part II. Effect of material, shade, and thickness on translucency.
abstract: BACKGROUND
  Information regarding the differences in translucency among new ceramic systems is lacking.
  
  
  OBJECTIVE
  The purpose of this study was to compare the relative translucency of the different types of ceramic systems indicated for porcelain veneers and to evaluate the effect of shade and thickness on translucency.
  
  
  METHODS
  Disk specimens 13 mm in diameter and 0.7-mm thick were fabricated for the following 9 materials (n=5): VITA VM9, IPS Empress Esthetic, VITA PM9, Vitablocks Mark II, Kavo Everest G-Blank, IPS Empress CAD, IPS e.max CAD, IPS e.maxPress, and Lava Zirconia. VITA VM9 served as the positive control and Lava as the negative control. The disks were fabricated with the shade that corresponds to A1. For IPS e.maxPress, additional disks were made with different shades (BL2, BL4, A1, B1, O1, O2, V1, V2, V3), thickness (0.3 mm), and translucencies (high translucency, low translucency). Color coordinates (CIE L∗ a∗ b∗) were measured with a tristimulus colorimeter. The translucency parameter was calculated from the color difference of the material on a black versus a white background. One-way ANOVA, the post hoc Tukey honestly significant difference, and the Ryan-Einot-Gabriel-Welsch multiple range tests were used to analyze the data (α=.05).
  
  
  RESULTS
  Statistically significant differences in the translucency parameter were found among porcelains (P<.001) according to the following rank: VM9>PM9, Empress Esthetic>Empress CAD>Mark II, Everest, e.max CAD>e.max Press>Lava. Significant differences also were noted when different shades and thickness were compared (P<.001).
  
  
  CONCLUSIONS
  Different ceramic systems designed for porcelain veneers present varying degrees of translucency. The thickness and shade of lithium disilicate ceramic affect its translucency. Shade affects translucency parameter less than thickness.
authors: Assistant Professor, Department of Restorative Dentistry, University of Colorado School of Dental Medicine, Aurora, Colo. Electronic address: karine.barizon@ucdenver.edu.
authors: Karine T L
authors: KT
authors: Barizon
authors: Associate Professor, Department of Operative Dentistry, Laval University Faculty of Dentistry.
authors: Cathia
authors: C
authors: Bergeron
authors: Professor, Department of Family Dentistry, The University of Iowa College of Dentistry, Iowa City, Iowa.
authors: Marcos A
authors: MA
authors: Vargas
authors: Associate Research Scientist/Adjunct Assistant Professor, Biostatistics Unit/Department of Preventive and Community Dentistry, The University of Iowa College of Dentistry, Iowa City, Iowa.
authors: Fang
authors: F
authors: Qian
authors: Associate Professor, Department of Operative Dentistry, The University of Iowa College of Dentistry, Iowa City, Iowa.
authors: Deborah S
authors: DS
authors: Cobb
authors: Associate Professor, Department of Prosthodontics, The University of Iowa College of Dentistry, Iowa City, Iowa.
authors: David G
authors: DG
authors: Gratton
authors: Associate Professor, Division of Operative Dentistry, University of Florida College of Dentistry, Gainesville, Fla.
authors: Saulo
authors: S
authors: Geraldeli
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D003116:Color; D003124:Colorimetry / Q000295:instrumentation; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry*; D003801:Dental Veneers; D006801:Humans; D008027:Light; D008422:Materials Testing; D017680:Potassium Compounds / Q000737:chemistry; D017797:Prosthesis Coloring; D013499:Surface Properties
chemical_list: D000538:Aluminum Silicates; D003764:Dental Materials; C520133:IPS e.max CAD LT; C508050:IPS e.max Press; C075815:IPS-Empress ceramic; D017680:Potassium Compounds; C493120:lithia disilicate; D003776:Dental Porcelain; C016447:feldspar