Characterization and effect of nanocomplexed fluoride solutions on the inhibition of enamel demineralization created by a multispecies cariogenic biofilm model.

OBJECTIVES

The aim of this study was to assess the in vitro caries preventive effect of nanocomplexed solutions of hydroxypropyl-β-cyclodextrin and γ-cyclodextrin associated with titanium tetrafluoride (TiF) after different complexation times (12 or 72 h).

MATERIALS AND METHODS

Enamel blocks were randomly distributed in 9 groups (n = 11): negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, TiF, hydroxypropyl-β-cyclodextrin:TiF 12 h, hydroxypropyl-β-cyclodextrin:TiF 72 h, γ-cyclodextrin:TiF 12 h, γ-cyclodextrin:TiF 72 h, and NaF (positive control). The solutions were applied for 1 min and the blocks were exposed to a biofilm model. Nanocompounds were characterized by differential scanning calorimetry and X-ray powder diffraction. The percentage of surface microhardness loss (%SML), mineral density changes (ΔZ), lesion depth, surface morphology (scanning electron microscopy-SEM), and chemical characterization (energy-dispersive spectroscopy-EDS) were assessed.

RESULTS

No oxidation was observed, and the formation of the nanocomplexes was evidenced by changes in the melting point compared to pure cyclodextrins and the loss of crystallinity of the materials. Hydroxypropyl-β-cyclodextrin:TiF 72 h resulted in lower %SML than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, and TiF (p < 0.05). NaF differed from all groups (p < 0.05), except for hydroxypropyl-β-cyclodextrin:TiF 72 h (p = 0.83). ΔZ of hydroxypropyl-β-cyclodextrin:TiF 72 h was higher than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, γ-cyclodextrin:TiF 1 2 h, γ-cyclodextrin:TiF 72 h, and NaF (p < 0.05) and similar to TiF and hydroxypropyl-β-cyclodextrin:TiF 12 h (p > 0.05). SEM/EDS detected Ti in the blocks subjected to TiF-products.

CONCLUSION

The hydroxypropyl-β-cyclodextrin:TiF 72 h solution showed caries preventive effect on the surface and subsurface of the enamel.

CLINICAL RELEVANCE

A hydroxypropyl-β-cyclodextrin nanosystem, in association with TiF after 72 h of complexation, may be a promising agent for the prevention of enamel demineralization.