Influence of surface treatments on adhesion of porcelain to titanium

This study evaluated the effect of etching solution surface treatments on the surface characteristics of titanium and adhesion of titanium/porcelain system by means of strain energy release rate (G-value, J/m²).

Two hundred and forty five specimens of cp Ti plates were prepared. The specimens were divided into five groups in each test according to the surface treatment used; Gr MC (machined control), Gr AP (airborne particle abrasion), Gr E15, Gr E30, and Gr E60 (etching solution applied for 15, 30, and 60 minutes, respectively). The treated surfaces were characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Three types of porcelains (Duceratin, Vita Titankeramik, Ti-22) were used to test adhesion with cp Ti. Following the four-point bending interfacial fracture test, the peeled fracture surfaces were examined using SEM. Data were analyzed using ANOVA and Tukey HSD test. Statistical significance was set at the 0.05 probability level.

AFM and SEM analyses showed that the surface topography of cp Ti was modified after treatments. Bond strength values were significantly affected by surface treatment and by type of porcelain (p < 0.05). The cp Ti/Duceratin (E30 and E60 minutes) groups showed the highest G-value among the groups. Modes of failure were mixed and interfacial adhesive.

Adhesion between cp Ti and porcelain could be enhanced by the use of experimental hot etching solution prior to porcelain firing as an alternative modality to the airborne-particle abrasion method.