Designing and milling of zirconia one-piece post-core restoration
ZirkonZahn blank(Prettau 2 Dispersive, Zirkonzahn Srl, Via An Der Ahr 7–39,030 Gais(Bz),Val Pusteria-South Tyrol–Italy)was used for the milling process to fabricate the zirconia post-core samples into the required dimensions, leaving 2-mm ferrule all around which permitted zirconia core to mimic same dimensions of composite cores in both groups GN and GW, by using ED5X(EMAR MILLS,C2, Industrial Complex, 10th of Ramadan City Asharqia, Egypt) milling machine, with prime water cooling system to produce one-piece post-core unit with respect to different diameters of tested groups (LN and LW). Nevertheless in this study, dry milling was performed in conjugation to dust extraction unit to vacuum any dust or particles resulting from the milling process. The milling process took about 10 minutes for each specimen, according to manufacturer’s instructions.