IADR Abstract Archives
Does Surface Topography Improve Electrochemical Behavior of Ti-6Al-4V Alloy in Different pH Saliva Levels?
Objectives: This study aimed to evaluate the potential of corrosion and microstructural changes of Ti-6Al-4V alloy, with a smooth surface or conditioned by double-acid-etching or aluminum oxide sandblasted in three pH saliva’s levels (3, 6.5 and 9).
Methods: For the electrochemical assay, open circuit potential, electrochemical impedance spectroscopy (EIS) and potentiodynamic test were used. Atomic force microscopy (AFM), Scanning electron microscopy (SEM), and profilometry (average roughness — Ra) were used for surface characterization. The corrosion parameters were compared by ANOVA and Tukey test (α =0.05).
Results: Similar values of corrosion potential (Ecorr) and corrosion current density (Icorr) were observed among groups (P> 0.05). For the pH = 3, aluminum oxide sandblasted disks promoted the highest passivation current density (Ipass) values (Tukey, P = 0.01). For the polarization resistance (Rp), the highest values were observed in the smooth surface compared with double-acid-etching surface of Ti-6Al-4V alloy (Tukey, P = 0.018). Aluminum oxide sandblasted disks promoted highest capacitance (Cdl) results (Tukey, P < 0.05). SEM and AFM images did not show any microstructural changes among the groups. Ra values did not shown any statistic difference among any of the situations tested (ANOVA, P = 0.284).
Conclusions: It could be concluded that higher corrosion rate was observed in the Ti-6Al-4V with aluminum oxide sandblasted surface exposed in pH = 3 saliva. Acid diets and systemic diseases that decrease salivary pH may have a greater tendency to implants corrosion.
Methods: For the electrochemical assay, open circuit potential, electrochemical impedance spectroscopy (EIS) and potentiodynamic test were used. Atomic force microscopy (AFM), Scanning electron microscopy (SEM), and profilometry (average roughness — Ra) were used for surface characterization. The corrosion parameters were compared by ANOVA and Tukey test (α =0.05).
Results: Similar values of corrosion potential (Ecorr) and corrosion current density (Icorr) were observed among groups (P> 0.05). For the pH = 3, aluminum oxide sandblasted disks promoted the highest passivation current density (Ipass) values (Tukey, P = 0.01). For the polarization resistance (Rp), the highest values were observed in the smooth surface compared with double-acid-etching surface of Ti-6Al-4V alloy (Tukey, P = 0.018). Aluminum oxide sandblasted disks promoted highest capacitance (Cdl) results (Tukey, P < 0.05). SEM and AFM images did not show any microstructural changes among the groups. Ra values did not shown any statistic difference among any of the situations tested (ANOVA, P = 0.284).
Conclusions: It could be concluded that higher corrosion rate was observed in the Ti-6Al-4V with aluminum oxide sandblasted surface exposed in pH = 3 saliva. Acid diets and systemic diseases that decrease salivary pH may have a greater tendency to implants corrosion.