Reinforcement of Bonding Strength between Dental Y‐TZP and Resin via Nano‐Thin and Conformal SiO2 Films by Atomic Layer Deposition

Abstract The retentive strength of zirconia crowns is derived from resin cement, and the weak interface between the two is the main reason for their failure. In this work, nano‐thin silica (SiO 2 ) films of precisely controlled thickness are deposited over yttrium‐stabilized tetragonal zirconia polycrystal (Y‐TZP) ceramics via atomic layer deposition (ALD). The deposited films are modified using a silane coupling agent, which significantly improves the bonding strength between Y‐TZP and resin. Scanning electron microscopy shows that the SiO 2 films deposited by ALD are uniform and can accurately maintain the morphology of grit‐blasted Y‐TZP. Spectroscopic ellipsometry demonstrates that the films are nano‐thin, with thicknesses in the range of 5.58–26.58 nm. The increase in the shear bond strength is attributed to the chemical bonding between the conformal nano‐SiO 2 films and Y‐TZP. However, the stability of the bond decreases when the SiO 2 films are too thick. Overall, the results indicate that SiO 2 films deposited in 400 ALD cycles have both good bonding strength and stability after aging, much higher than those of Z‐Prime Plus films.