Effect of Incisal Porcelain Veneering Thickness on the Fracture Resistance of CAD/CAM Zirconia All-Ceramic Anterior Crowns

Table 1

Crown materials used in this study.

System	System	Metal ceramic
(1) Coping material	Zirkonzahn partially sintered zirconia blank	Nickel-chromium alloy art alloy BF
Fabrication technique	CAD/CAM	Lost wax technique
Composition	Main component is zirconium dioxide (ZrO2) + yttrium oxide (Y2O3 5%); Hafnium oxide (Hf2O3 < 2%); Aluminium oxide + silicon oxide < 1%	Ni 62%; Cr 23.5%; Mo 10%; Components less than 2% are Si, Mn, Nb, and Ti
(2) Veneering material	Porcelain for zirconia Ceramco®PFZ	Porcelain for nickel-chromium alloy Ceramco 3
Fabrication technique	Layering technique	Layering technique
Composition	Feldspathic porcelain containing no leucite	Feldspathic porcelain containing 0.30 volume fraction leucite

Zirkonzahn, GmbH, Bruneck, Italy. Mesa di sala Giacomo and C-Snc-PI: 00623390176, Travagliato (BRESCIA), Italia (http://www.mesaitalia.com). Dentsply International Inc., York, USA (http://www.ceramco.com and http://www.densply.com).