Background:
The titanium (Ti) is the main element of dental implants (Ti) and has a strong bond with water or air molecules in the atmosphere, which promotes the immediate formation of a Ti oxide layer on the surface. However, changes in periimplantar electrolytic environment, such as pH and thermal oscillations, and the presence of biofilm, inflammation and hyperglycemia conditions can degrade the oxide layer, allowing for the exchange of Ti ions. This activity contributes to the corrosion process of the implant surface. Hyperglycemia leads to overproduction of superoxide, wich contributes to the pathogenesis of diabetic micro- and macrovascular complications.
Aim/Hypothesis:
The aim of this study was to analyze the corrosion behavior of Ti-6Al-4V with different surfaces (machined and modified by treatment with double acid-etching), on simulator body fluids (SBF) with different concentrations of dextrose (0; 5 mM, 7.5 mM and 15 mM) and lipopolysaccharide (LPS) (0; 0.15 µg/mL; 15 µg/mL; 150 µg/mL), used isolated or in combination.
Material and Methods:
Ti-6Al-4V disks (2 mm in thickness and 15 mm in diameter) were fabricated with different surfaces. For electrochemical assay (n = 3), open circuit potential, electrochemical impedance spectroscopy (EIS) and potentiodynamic tests were conducted in SBF with different concentrations of dextrose and LPS. The surfaces of the disks were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by surface roughness and microhardness. Data were analyzed by Pearson correlation and independent t-test at a significant level of 5%.
Results:
For the corrosion parameters, a strong correlation of LPS with Ipass (passivation current density), Cdl (capacitance) and Rp (polarization resistance) values (P <.05) for Ti surface treated by double acid- etching was noted. The combination of dextrose and LPS was correlated with Ipass and Icorr (corrosion current density) (P <.05). Regarding the corrosion kinetics the acid-treated groups showed significant increase in Cdl values and reduced values of Rp (P <.05, T-test). In terms of topography, there was an increase in surface roughness for both surfaces (R2 = 0.726, p = 0.0001 for machined Ti, R2 = 0.405, p = 0.036 for Ti acid). The machined Ti exhibited reduction in microhardness (P <.05), while Ti acid showed increased microhardness (p = 0.0001) vs baseline. The AFM showed changes in the microstructure of Ti by increasing the thickness of surface mainly in the association of dextrose and LPS.
Conclusions and clinical implications:
The combination of dextrose and LPS affected the corrosion behavior of Ti-6Al-4V surface treated with double acid-etching. These results indicate greater susceptibility of Ti implants to corrosion in diabetic patients with associated infections.
Background:
The titanium (Ti) is the main element of dental implants (Ti) and has a strong bond with water or air molecules in the atmosphere, which promotes the immediate formation of a Ti oxide layer on the surface. However, changes in periimplantar electrolytic environment, such as pH and thermal oscillations, and the presence of biofilm, inflammation and hyperglycemia conditions can degrade the oxide layer, allowing for the exchange of Ti ions. This activity contributes to the corrosion process of the implant surface. Hyperglycemia leads to overproduction of superoxide, wich contributes to the pathogenesis of diabetic micro- and macrovascular complications.
Aim/Hypothesis:
The aim of this study was to analyze the corrosion behavior of Ti-6Al-4V with different surfaces (machined and modified by treatment with double acid-etching), on simulator body fluids (SBF) with different concentrations of dextrose (0; 5 mM, 7.5 mM and 15 mM) and lipopolysaccharide (LPS) (0; 0.15 µg/mL; 15 µg/mL; 150 µg/mL), used isolated or in combination.
Material and Methods:
Ti-6Al-4V disks (2 mm in thickness and 15 mm in diameter) were fabricated with different surfaces. For electrochemical assay (n = 3), open circuit potential, electrochemical impedance spectroscopy (EIS) and potentiodynamic tests were conducted in SBF with different concentrations of dextrose and LPS. The surfaces of the disks were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by surface roughness and microhardness. Data were analyzed by Pearson correlation and independent t-test at a significant level of 5%.
Results:
For the corrosion parameters, a strong correlation of LPS with Ipass (passivation current density), Cdl (capacitance) and Rp (polarization resistance) values (P <.05) for Ti surface treated by double acid- etching was noted. The combination of dextrose and LPS was correlated with Ipass and Icorr (corrosion current density) (P <.05). Regarding the corrosion kinetics the acid-treated groups showed significant increase in Cdl values and reduced values of Rp (P <.05, T-test). In terms of topography, there was an increase in surface roughness for both surfaces (R2 = 0.726, p = 0.0001 for machined Ti, R2 = 0.405, p = 0.036 for Ti acid). The machined Ti exhibited reduction in microhardness (P <.05), while Ti acid showed increased microhardness (p = 0.0001) vs baseline. The AFM showed changes in the microstructure of Ti by increasing the thickness of surface mainly in the association of dextrose and LPS.
Conclusions and clinical implications:
The combination of dextrose and LPS affected the corrosion behavior of Ti-6Al-4V surface treated with double acid-etching. These results indicate greater susceptibility of Ti implants to corrosion in diabetic patients with associated infections.
Background:
The titanium (Ti) is the main element of dental implants (Ti) and has a strong bond with water or air molecules in the atmosphere, which promotes the immediate formation of a Ti oxide layer on the surface. However, changes in periimplantar electrolytic environment, such as pH and thermal oscillations, and the presence of biofilm, inflammation and hyperglycemia conditions can degrade the oxide layer, allowing for the exchange of Ti ions. This activity contributes to the corrosion process of the implant surface. Hyperglycemia leads to overproduction of superoxide, wich contributes to the pathogenesis of diabetic micro- and macrovascular complications.
Aim/Hypothesis:
The aim of this study was to analyze the corrosion behavior of Ti-6Al-4V with different surfaces (machined and modified by treatment with double acid-etching), on simulator body fluids (SBF) with different concentrations of dextrose (0; 5 mM, 7.5 mM and 15 mM) and lipopolysaccharide (LPS) (0; 0.15 µg/mL; 15 µg/mL; 150 µg/mL), used isolated or in combination.
Material and Methods:
Ti-6Al-4V disks (2 mm in thickness and 15 mm in diameter) were fabricated with different surfaces. For electrochemical assay (n = 3), open circuit potential, electrochemical impedance spectroscopy (EIS) and potentiodynamic tests were conducted in SBF with different concentrations of dextrose and LPS. The surfaces of the disks were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by surface roughness and microhardness. Data were analyzed by Pearson correlation and independent t-test at a significant level of 5%.
Results:
For the corrosion parameters, a strong correlation of LPS with Ipass (passivation current density), Cdl (capacitance) and Rp (polarization resistance) values (P <.05) for Ti surface treated by double acid- etching was noted. The combination of dextrose and LPS was correlated with Ipass and Icorr (corrosion current density) (P <.05). Regarding the corrosion kinetics the acid-treated groups showed significant increase in Cdl values and reduced values of Rp (P <.05, T-test). In terms of topography, there was an increase in surface roughness for both surfaces (R2 = 0.726, p = 0.0001 for machined Ti, R2 = 0.405, p = 0.036 for Ti acid). The machined Ti exhibited reduction in microhardness (P <.05), while Ti acid showed increased microhardness (p = 0.0001) vs baseline. The AFM showed changes in the microstructure of Ti by increasing the thickness of surface mainly in the association of dextrose and LPS.
Conclusions and clinical implications:
The combination of dextrose and LPS affected the corrosion behavior of Ti-6Al-4V surface treated with double acid-etching. These results indicate greater susceptibility of Ti implants to corrosion in diabetic patients with associated infections.
Background:
The titanium (Ti) is the main element of dental implants (Ti) and has a strong bond with water or air molecules in the atmosphere, which promotes the immediate formation of a Ti oxide layer on the surface. However, changes in periimplantar electrolytic environment, such as pH and thermal oscillations, and the presence of biofilm, inflammation and hyperglycemia conditions can degrade the oxide layer, allowing for the exchange of Ti ions. This activity contributes to the corrosion process of the implant surface. Hyperglycemia leads to overproduction of superoxide, wich contributes to the pathogenesis of diabetic micro- and macrovascular complications.
Aim/Hypothesis:
The aim of this study was to analyze the corrosion behavior of Ti-6Al-4V with different surfaces (machined and modified by treatment with double acid-etching), on simulator body fluids (SBF) with different concentrations of dextrose (0; 5 mM, 7.5 mM and 15 mM) and lipopolysaccharide (LPS) (0; 0.15 µg/mL; 15 µg/mL; 150 µg/mL), used isolated or in combination.
Material and Methods:
Ti-6Al-4V disks (2 mm in thickness and 15 mm in diameter) were fabricated with different surfaces. For electrochemical assay (n = 3), open circuit potential, electrochemical impedance spectroscopy (EIS) and potentiodynamic tests were conducted in SBF with different concentrations of dextrose and LPS. The surfaces of the disks were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by surface roughness and microhardness. Data were analyzed by Pearson correlation and independent t-test at a significant level of 5%.
Results:
For the corrosion parameters, a strong correlation of LPS with Ipass (passivation current density), Cdl (capacitance) and Rp (polarization resistance) values (P <.05) for Ti surface treated by double acid- etching was noted. The combination of dextrose and LPS was correlated with Ipass and Icorr (corrosion current density) (P <.05). Regarding the corrosion kinetics the acid-treated groups showed significant increase in Cdl values and reduced values of Rp (P <.05, T-test). In terms of topography, there was an increase in surface roughness for both surfaces (R2 = 0.726, p = 0.0001 for machined Ti, R2 = 0.405, p = 0.036 for Ti acid). The machined Ti exhibited reduction in microhardness (P <.05), while Ti acid showed increased microhardness (p = 0.0001) vs baseline. The AFM showed changes in the microstructure of Ti by increasing the thickness of surface mainly in the association of dextrose and LPS.
Conclusions and clinical implications:
The combination of dextrose and LPS affected the corrosion behavior of Ti-6Al-4V surface treated with double acid-etching. These results indicate greater susceptibility of Ti implants to corrosion in diabetic patients with associated infections.