Zirconium oxide bridges or crowns are now perfectly manufactured by various manufacturers using CAD CAM technology. The high quality of zirconium is characterized by very high strength, toughness and wear resistance. This makes the requirements for cutting zirconium crowns or bridges even greater. Due to the nature of the material, fine and very fine grains are more efficient in removing material. However, if the zirconium crown has a veneer ceramic, the requirements for the grain of the rotating instrument change.