AZDENT 5pcs/Box Lithium Disilicate C14 Glass Ceramic Blocks LT/HT Dental Lab Crown Material for CAD CAM Sirona Cerec Milling Syste. Bending strength The average biaxial bending strength after being fully crystallized is 637Mpa, higher than the standard strength value, set by ISO6892:2008 For Dental Ceramics.