Electrochemical analysis of the degradation of nitrided zirconia 3Y-TZP

Abstract

Zirconia is a material that is susceptible to changes in its structure from the tetragonal to the monoclinic phase caused by variations in temperature or by contact with water. One way of achieving the stability of the tetragonal phase at low temperatures is by incorporating anionic gaps in its crystal lattice through doping procedures with aliovalent anions such as nitrogen. Nitrogen replaces the oxygen in the crystal lattice, which stabilizes the tetragonal structure of zirconia at low temperatures. The aim of this research was to evaluate the degradation of nitrided zirconia 3Y-TZP after it was immersed in artificial saliva for 0, 7, 14, and 21 days. Interfacial processes such as oxide-formation were assessed simultaneously using the electrochemical impedance spectroscopy test. Additionally, morphological, topographic, and composition changes were analyzed in the degradation process using SEM-EDS and AFM.