Effect of TiO2-SiO2-SnOx sol-gel coating on the bonding strength of titanium-porcelain

Abstract

Effect of TiO2-SiO2-SnOx sol-gel coating burnt at 300°C on the cpTi-porcelain bond strength was investigated in this study. Before the porcelain was fused, the phase, surface morphology, and static water contact angle of the intermediate layer were evaluated. The cpTi-porcelain bond strength was measured using the three-point flexure test according to ISO 9693 standard. The surface morphology of titanium surface debonded from porcelain was evaluated with a scanning electron microscope. Statistical analysis was made with an independent samples t test. No rutile phase was found in the tested specimen coated with TiO2-SiO2-SnOx sol-gel coating. The cpTi-porcelain bond strength of coated group (35.7±2.65MPa) was significantly higher than that of noncoated group (31.7±3.52MPa). Statistical difference of static water contact angle was found between the two groups. The surface morphology of the intermediate layer was compact and homogeneous with visible cracks. Sn element was found in the titanium surface after the porcelain was debonded, which indicated that the fracture mode of titanium-porcelain system might have been changed. The results show that the TiO2-SiO2-SnOx sol-gel coating burnt at 300°C can improve the bond strength of titanium to porcelain.