IADR Abstract Archives
The effect of titaniumdioxide-nanotubes on flowable-composite's physical, mechanical, antibacterial properties
Objectives: To evaluate flowable-composite’s antibacterial activity against Streptococcus mutans, surface roughness, shear bond strength against enamel and dentin by adding various percents of titaniumdioxide-nanotubes.
Methods: Titaniumdioxide-nanotubes were synthesized by hydrothermal treatment. The functionalized groups were characterized by FTIR. Prepared nanotubes were added in the flowable composite Delete flow lv with various percentages(0.5, 1, 1,5, 2% by weight). (I)Biofilm test was done to assess the antibacterial effect of nanotubes. Disc-shaped specimens were prepared for every group(n=12) and the half of the specimens were exposed to ultraviolet light. All specimens were incubated with Streptococcus mutans and biofilm formed on the specimens were assessed. (II)Disc-shaped specimens were prepared for every group(n=12) and polished. The surface roughness was measured by optic profilometry. (III)Specimens were put through shear bond strength test. 150 extracted human premolar teeth were used. The teeth were randomly divided into two groups, flattened with sandpaper exposing enamel in first group and dentin in second group. Specimens in enamel and dentin groups(n=15) were etched with acid and then composite specimens(Aelite flo lv) were bonded to teeth with the etch-and-rinse adhesive (One step).Specimens were tested in shear strength in a universal testing machine. Stereomicroscope was used to analyze the samples’ fracture mode. Data were analyzed statistically.
Results: Ultraviolet improved TiO2-nanotubes antibacterial effect(p<0.05). Increase in the percentage of TiO2 decreased the biofilm. Antibacterial activity was not observed on the specimens that were not exposed to ultraviolet. The highest surface roughness was measured in the 2% TiO2 resin group, there was no significant difference between the other groups(p<0.05). The addition of increasing percentages of TiO2-nanotube, reduced enamel bond strength forces(p<0.05).
Conclusions: Adding nanotubes to composite resin didn’t effect the bond strength to dentin. Containing TiO2-nanotube composite exposed to ultraviolet-light showed antibacterial activity, low amounts of nanotubes added to the resin didn’t affect the physical and mechanical properties.
Methods: Titaniumdioxide-nanotubes were synthesized by hydrothermal treatment. The functionalized groups were characterized by FTIR. Prepared nanotubes were added in the flowable composite Delete flow lv with various percentages(0.5, 1, 1,5, 2% by weight). (I)Biofilm test was done to assess the antibacterial effect of nanotubes. Disc-shaped specimens were prepared for every group(n=12) and the half of the specimens were exposed to ultraviolet light. All specimens were incubated with Streptococcus mutans and biofilm formed on the specimens were assessed. (II)Disc-shaped specimens were prepared for every group(n=12) and polished. The surface roughness was measured by optic profilometry. (III)Specimens were put through shear bond strength test. 150 extracted human premolar teeth were used. The teeth were randomly divided into two groups, flattened with sandpaper exposing enamel in first group and dentin in second group. Specimens in enamel and dentin groups(n=15) were etched with acid and then composite specimens(Aelite flo lv) were bonded to teeth with the etch-and-rinse adhesive (One step).Specimens were tested in shear strength in a universal testing machine. Stereomicroscope was used to analyze the samples’ fracture mode. Data were analyzed statistically.
Results: Ultraviolet improved TiO2-nanotubes antibacterial effect(p<0.05). Increase in the percentage of TiO2 decreased the biofilm. Antibacterial activity was not observed on the specimens that were not exposed to ultraviolet. The highest surface roughness was measured in the 2% TiO2 resin group, there was no significant difference between the other groups(p<0.05). The addition of increasing percentages of TiO2-nanotube, reduced enamel bond strength forces(p<0.05).
Conclusions: Adding nanotubes to composite resin didn’t effect the bond strength to dentin. Containing TiO2-nanotube composite exposed to ultraviolet-light showed antibacterial activity, low amounts of nanotubes added to the resin didn’t affect the physical and mechanical properties.