H I P

The method of hot isostatic postcompaction is used today as a standard for improving characteristics relevant to fracture mechanics in ceramic implants. HIPing reduces porosity, increases density and purity, and thus leads to a relevant increase in long-term life expectancy and a decrease in the tendency to sub-critical crack growth.

(Wolfhart Rieger, Stefan Köbel, Wolfram Weber: Processing and properties of Zirconia Ceramics for Dental Applications)