Pre-sintered Zirconia is porous (48%) and absorbs processing water or dyeing liquids on the basis of the milling and immersion time.
Zirconia products must be properly dried before being placed in the sintering kiln. The product may be dried after wet processing or dyeing with a fan heater at a temperature between 80° and 100 °C, for a time which varies depending on the thickness of the dental prosthesis. Drying time ranges from 30 minutes to 2 hours.
An infrared lamp may also be used. Alternatively, the product may be dried in the sintering kiln in the one-step drying cycle at 150°C for at least 30 minutes.