Research progress in surface bonding pretreatment of dental zirconia ceramics

Yttria stabilized tetragonal zirconia polycrystal ceramics is widely used in the field of dentistry because of its excellent mechanical properties and biocompatibility. However, it has low hydroxyl content and does not contain silica. Therefore micro mechanical retention induced by hydrofluoric acid etching on its surface is not applicable. The bonding of zirconia is a difficult problem. Zirconia surface pretreatment is commonly used to improve bonding strength and durability. This review summarizes surface pretreatment of dental zirconia ceramic including air abrasion, laser etching, acid etching, silica coating, non-thermal plasmas treatment, et al. In addition, it presents advantages and disadvantages of each treatment, provides guidance for application and future research directions.