Chemical durability of high translucent dental zirconia

This review describes low temperature degradation (LTD), discoloration, and erosion of high translucent dental zirconia and discusses its chemical durability in comparison with other CAD/CAM materials. The LTD of zirconia strongly depended on the firing temperature, yttria content, surface treatment, and heat treatment. Glass ceramics for CAD/CAM were remarkably etched in a lactic acid at 60 degrees C, KOH solution at 60 degrees C, and saline solution at 90 degrees C, whereas zirconia showed no changes in these solutions. Glass ceramics and hybrid resins for CAD/CAM showed significant discoloration in a red wine and rhodamine B solution at 37 degrees C, whereas zirconia showed no discolorations in either solution. It was concluded that high translucent dental zirconia has the highest chemical durability among dental CAD/CAM materials.