Fracture resistance of zirconia crowns depending on different preparation designs. An in vitro study - Stavreva N, Kapusevska B, Zabokova-Bilbilova E, Kokoceva Ivanovska O, Pisevska Gerasimova S, Toseska Spasova N. (18 Kongres stomatologa Srbije sa međunarodnim ucescem, 2019)