TiO2 nanotube-based nanotechnology applied to high-viscosity conventional glass-ionomer cement: ultrastructural analyses and physicochemical characterization

This study characterized TiO2 nanotube (TiO2-nt) ultrastructure and morphology, and the physicochemical impact on high-viscosity conventional glass-ionomer cement (GIC). TiO2-nt was synthesized by the alkaline method (n = 3), assessed by scanning (SEM) and transmission electron microscope (TEM), and was added (3%, 5%, 7%—in weight) to KM (Ketac Molar EasyMix™). Analyses included: SEM; Energy-dispersive spectroscopy (EDS); Raman spectroscopy (RAMAN); Setting time with Gillmore needles (ST); Color (Co); Radiopacity (XR); Water sorption (WS); and solubility (SO). Quantitative data were submitted to ANOVA and Tukey’s tests (chr = 0.05). External and internal TiO2-nt diameters were 11 ± 2 nm and 6 ± 0 nm, respectively. Data analyses showed: (i) TiO2-nt present into KM matrix, with a concentration-dependent increase of Ti levels into KM, (ii) physical interaction between KM and TiO2-nt, (iii) longer initial ST for the 7% group compared to KM and 3% groups (p ≤ 0.01), (iv) decreased luminosity and yellowness for the 5% and 7% groups, (v) 36% greater radiopacity for the 5% group compared to enamel, dentin, and KM, and (vi) lower SO values for the 5% group, with no significant differences on WS across the groups. TiO2-nt displayed physical interaction with KM matrix, and also modified SO, XR and Co, without affecting ST. This study provides information on the potential impact of TiO2-nt on GIC performance. TiO2-nt may be proposed to boost confidence among dental surgeons in terms of GIC’s handling characteristics, success rate and differential diagnostic.