RESUMO
BACKGROUND: Berries are known for their antioxidant activity due to the presence of flavonoids. Antioxidants' usage guarantees skin protection against free radicals and, flavonoids, especially, can act as sunscreen. The aim of this paper was to evaluate solar protection factor (SPF) and antioxidant activity in vitro of blackberry and raspberry extracts incorporated in topical formulation and study their stability. RESULTS: Raspberry presented 29.93 mg of anthocyanins/100 g of fruit and blackberry 65.58 mg of anthocyanins/100 g of fruit. In vitro solar protection factor was 54.57 to blackberry and 37.32 to raspberry. When incorporated in O/W emulsions, final formulations showed light pink color, creamy aspect, and typical fruity odor. Formulations submitted to indirect light and stove showed odor and color alterations. CONCLUSIONS: Based on the results, formulations containing extracts should be kept under refrigeration in opaque package to ensure stability due to the presence of flavonoids. In addition, blackberry and raspberry extracts are potential natural alternatives to be used as sunscreen and to prevent skin aging.
Assuntos
Antocianinas/química , Antioxidantes/química , Extratos Vegetais/química , Rubus/química , Protetores Solares/química , Antocianinas/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Compostos de Bifenilo/efeitos da radiação , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Frutas/química , Humanos , Oxirredução/efeitos da radiação , Picratos/química , Picratos/efeitos da radiação , Extratos Vegetais/isolamento & purificação , Quercetina/química , Quercetina/efeitos da radiação , Espectrofotometria , Fator de Proteção Solar , Protetores Solares/isolamento & purificação , Raios UltravioletaRESUMO
The aim of this study was to analyze the efficiency of experimental light-curing resin cements (ERCs) with a ternary photo-initiator system containing diphenyliodonium hexafluorphosphate (DPI) and different amines on retention of glass-fiber posts to dentin (GFP). ERCs formulations: a 1:1 mass ratio of 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenylpropane and triethyleneglycol dimethacrylate. Camphorquinone was used as initiator. Six experimental groups were established according to the amine used: [ethyl-4-(dimethylamino)benzoate-EDMAB or 2-(dimethylamino)ethyl methacrylate-DMAEMA] and the concentration of DPI (0, 0.5 mol%, 1 mol%). The resin cements Variolink II (dual- and light-cured versions) were used as commercial reference. Eighty recently extracted bovine incisors (n = 10) were selected for this study. The roots were prepared and the fiber posts were cemented with the resin cement specified for each experimental group. Specimens from coronal, middle, and apical thirds of the root were subjected to push-out bond strength test 24 hours after bonding. Data were subjected to split-plot ANOVA and the Tukey test (p = 0.05). ERCs containing DPI showed statistically significant higher bond strengths compared with ERCs without DPI. ERCs containing DPI were statistically similar to VARIOLINK II - dual-cured and superior to VARIOLINK II - light-cured (except for EDMAB - 1DPI in the medium third and DMAEMA - 1DPI in the coronal third). Different amines did not influence post retention. The apical root region showed the lowest bond strength for the groups EDAB-0DPI, DMAEMA-0DPI and VARIOLINK II light-cured. Light-cured ERCs containing DPI were efficient for GFP retention to radicular dentin, with similar behaviour to that of dual-curing commercial resin cement.
Assuntos
Compostos de Bifenilo/química , Dentina/efeitos dos fármacos , Cura Luminosa de Adesivos Dentários/métodos , Oniocompostos/química , Fotoiniciadores Dentários/química , Técnica para Retentor Intrarradicular , Cimentos de Resina/química , Ápice Dentário/efeitos dos fármacos , Análise de Variância , Compostos de Bifenilo/efeitos da radiação , Lâmpadas de Polimerização Dentária , Dentina/efeitos da radiação , Vidro/química , Vidro/efeitos da radiação , Teste de Materiais , Metacrilatos/química , Metacrilatos/efeitos da radiação , Oniocompostos/efeitos da radiação , Fotoiniciadores Dentários/efeitos da radiação , Polimerização , Cimentos de Resina/efeitos da radiação , Fatores de Tempo , Ápice Dentário/efeitos da radiação , Fraturas dos Dentes , para-Aminobenzoatos/química , para-Aminobenzoatos/efeitos da radiaçãoRESUMO
Abstract The aim of this study was to analyze the efficiency of experimental light-curing resin cements (ERCs) with a ternary photo-initiator system containing diphenyliodonium hexafluorphosphate (DPI) and different amines on retention of glass-fiber posts to dentin (GFP). ERCs formulations: a 1:1 mass ratio of 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenylpropane and triethyleneglycol dimethacrylate. Camphorquinone was used as initiator. Six experimental groups were established according to the amine used: [ethyl-4-(dimethylamino)benzoate-EDMAB or 2-(dimethylamino)ethyl methacrylate-DMAEMA] and the concentration of DPI (0, 0.5 mol%, 1 mol%). The resin cements Variolink II (dual- and light-cured versions) were used as commercial reference. Eighty recently extracted bovine incisors (n = 10) were selected for this study. The roots were prepared and the fiber posts were cemented with the resin cement specified for each experimental group. Specimens from coronal, middle, and apical thirds of the root were subjected to push-out bond strength test 24 hours after bonding. Data were subjected to split-plot ANOVA and the Tukey test (p = 0.05). ERCs containing DPI showed statistically significant higher bond strengths compared with ERCs without DPI. ERCs containing DPI were statistically similar to VARIOLINK II - dual-cured and superior to VARIOLINK II - light-cured (except for EDMAB - 1DPI in the medium third and DMAEMA - 1DPI in the coronal third). Different amines did not influence post retention. The apical root region showed the lowest bond strength for the groups EDAB-0DPI, DMAEMA-0DPI and VARIOLINK II light-cured. Light-cured ERCs containing DPI were efficient for GFP retention to radicular dentin, with similar behaviour to that of dual-curing commercial resin cement.
Assuntos
Oniocompostos/química , Compostos de Bifenilo/química , Técnica para Retentor Intrarradicular , Ápice Dentário/efeitos dos fármacos , Cimentos de Resina/química , Dentina/efeitos dos fármacos , Cura Luminosa de Adesivos Dentários/métodos , Fotoiniciadores Dentários/química , Oniocompostos/efeitos da radiação , Fatores de Tempo , Fraturas dos Dentes , Compostos de Bifenilo/efeitos da radiação , Teste de Materiais , Análise de Variância , Ápice Dentário/efeitos da radiação , Cimentos de Resina/efeitos da radiação , Dentina/efeitos da radiação , Lâmpadas de Polimerização Dentária , Fotoiniciadores Dentários/efeitos da radiação , Polimerização , para-Aminobenzoatos/efeitos da radiação , para-Aminobenzoatos/química , Vidro/efeitos da radiação , Vidro/química , Metacrilatos/efeitos da radiação , Metacrilatos/químicaRESUMO
OBJECTIVES: The purpose of this study was to evaluate the reactivity and polymerization kinetics behavior of a model dental adhesive resin with water-soluble initiator systems. METHODS: A monomer blend based on Bis-GMA, TEGDMA and HEMA was used as a model dental adhesive resin, which was polymerized using a thioxanthone type (QTX) as a photoinitiator. Binary and ternary photoinitiator systems were formulated using 1mol% of each initiator. The co-initiators used in this study were ethyl 4-dimethylaminobenzoate (EDAB), diphenyliodonium hexafluorophosphate (DPIHFP), 1,3-diethyl-2-thiobarbituric acid (BARB), p-toluenesulfinic acid and sodium salt hydrate (SULF). Absorption spectra of the initiators were measured using a UV-Vis spectrophotometer, and the photon absorption energy (PAE) was calculated. The binary system camphorquinone (CQ)/amine was used as a reference group (control). Twelve groups were tested in triplicate. Fourier-transform infrared spectroscopy (FTIR) was used to investigate the polymerization reaction during the photoactivation period to obtain the degree of conversion (DC) and maximum polymerization rate (R(p)(max)) profile of the model resin. RESULTS: In the analyzed absorption profiles, the absorption spectrum of QTX is almost entirely localized in the UV region, whereas that of CQ is in the visible range. With respect to binary systems, CQ+EDAB exhibited higher DC and R(p)(max) values. In formulations that contained ternary initiator systems, the group CQ+QTX+EDAB was the only one of the investigated experimental groups that exhibited an R(p)(max) value greater than that of CQ+EDAB. The groups QTX+EDAB+DPIHFP and QTX+DPIHFP+SULF exhibited values similar to those of CQ+EDAB with respect to the final DC; however, they also exhibited lower reactivity. SIGNIFICANCE: Water-soluble initiator systems should be considered as alternatives to the widely used CQ/amine system in dentin adhesive formulations.