Thiago I Vieira1, Adílis K Alexandria1, Jaqueline C V Menezes2, Lilian H do Amaral2, Thaís M P Dos Santos3, Aline de A Neves1,4, Ricardo T Lopes3, Lúcio M Cabral2, Ana M G Valença5, Lucianne C Maia6. 1. Department of Paediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. 2. School of Pharmacy, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. 3. Laboratory for Nuclear Instrumentation, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. 4. Clinical Lecturer in Paediatric Dentistry, King's College London, London, UK. 5. Department of Clinic and Social Dentistry, School of Dentistry, Universidade Federal da Paraíba, Joao Pessoa, Paraíba, Brazil. 6. Department of Paediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. rorefa@terra.com.br.
Abstract
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 (TiF4) 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, TiF4, hydroxypropyl-β-cyclodextrin:TiF4 12 h, hydroxypropyl-β-cyclodextrin:TiF4 72 h, γ-cyclodextrin:TiF4 12 h, γ-cyclodextrin:TiF4 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:TiF4 72 h resulted in lower %SML than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, and TiF4 (p < 0.05). NaF differed from all groups (p < 0.05), except for hydroxypropyl-β-cyclodextrin:TiF4 72 h (p = 0.83). ΔZ of hydroxypropyl-β-cyclodextrin:TiF4 72 h was higher than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, γ-cyclodextrin:TiF4 1 2 h, γ-cyclodextrin:TiF4 72 h, and NaF (p < 0.05) and similar to TiF4 and hydroxypropyl-β-cyclodextrin:TiF4 12 h (p > 0.05). SEM/EDS detected Ti in the blocks subjected to TiF4-products. CONCLUSION: The hydroxypropyl-β-cyclodextrin:TiF4 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 TiF4 after 72 h of complexation, may be a promising agent for the prevention of enamel demineralization.
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 (TiF4) 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, TiF4, hydroxypropyl-β-cyclodextrin:TiF4 12 h, hydroxypropyl-β-cyclodextrin:TiF4 72 h, γ-cyclodextrin:TiF4 12 h, γ-cyclodextrin:TiF4 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:TiF4 72 h resulted in lower %SML than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, and TiF4 (p < 0.05). NaF differed from all groups (p < 0.05), except for hydroxypropyl-β-cyclodextrin:TiF4 72 h (p = 0.83). ΔZ of hydroxypropyl-β-cyclodextrin:TiF4 72 h was higher than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, γ-cyclodextrin:TiF4 1 2 h, γ-cyclodextrin:TiF4 72 h, and NaF (p < 0.05) and similar to TiF4 and hydroxypropyl-β-cyclodextrin:TiF4 12 h (p > 0.05). SEM/EDS detected Ti in the blocks subjected to TiF4-products. CONCLUSION: The hydroxypropyl-β-cyclodextrin:TiF4 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 TiF4 after 72 h of complexation, may be a promising agent for the prevention of enamel demineralization.