RESUMEN
Iontophoresis is a noninvasive technique, based on the application of a constant low-intensity electric current to facilitate the release of a variety of drugs, whether ionized or not, through biological membranes. The objective of this research was to evaluate the effect of iontophoresis using different electric current intensities on the uptake of fluoride in dental enamel with artificial caries lesions. In this in vitro operator-blind experiment, bovine enamel blocks (n = 10/group) with caries-like lesions and predetermined surface hardness were randomized into 6 groups: placebo gel without fluoride applied with a current of 0.8 mA (negative control), 2% NaF gel without application of any current, and 2% NaF gel applied with currents of 0.1, 0.2, 0.4 and 0.8 mA. Cathodic iontophoresis was applied for 4 min. The concentration of loosely bound fluoride (calcium fluoride) and firmly bound fluoride (fluorapatite) was determined. The results were analyzed by the nonparametric Kruskal-Wallis and Dunn tests. Iontophoresis at 0.8 mA, combined with the application of fluoridated gel (2% NaF), increased fluoride uptake in enamel with caries-like lesions, as either calcium fluoride or fluorapatite.
Asunto(s)
Cariostáticos/farmacología , Caries Dental , Esmalte Dental/efectos de los fármacos , Fluoruros/farmacología , Iontoforesis/métodos , Animales , Apatitas/análisis , Fluoruro de Calcio/análisis , Bovinos , Modelos Animales de Enfermedad , Electricidad , Dureza/efectos de los fármacos , Distribución Aleatoria , Propiedades de Superficie/efectos de los fármacos , Resultado del TratamientoRESUMEN
Abstract: Iontophoresis is a noninvasive technique, based on the application of a constant low-intensity electric current to facilitate the release of a variety of drugs, whether ionized or not, through biological membranes. The objective of this research was to evaluate the effect of iontophoresis using different electric current intensities on the uptake of fluoride in dental enamel with artificial caries lesions. In this in vitro operator-blind experiment, bovine enamel blocks (n = 10/group) with caries-like lesions and predetermined surface hardness were randomized into 6 groups: placebo gel without fluoride applied with a current of 0.8 mA (negative control), 2% NaF gel without application of any current, and 2% NaF gel applied with currents of 0.1, 0.2, 0.4 and 0.8 mA. Cathodic iontophoresis was applied for 4 min. The concentration of loosely bound fluoride (calcium fluoride) and firmly bound fluoride (fluorapatite) was determined. The results were analyzed by the nonparametric Kruskal-Wallis and Dunn tests. Iontophoresis at 0.8 mA, combined with the application of fluoridated gel (2% NaF), increased fluoride uptake in enamel with caries-like lesions, as either calcium fluoride or fluorapatite.
Asunto(s)
Animales , Bovinos , Cariostáticos/farmacología , Iontoforesis/métodos , Caries Dental , Esmalte Dental/efectos de los fármacos , Fluoruros/farmacología , Apatitas/análisis , Propiedades de Superficie/efectos de los fármacos , Fluoruro de Calcio/análisis , Distribución Aleatoria , Resultado del Tratamiento , Modelos Animales de Enfermedad , Electricidad , Dureza/efectos de los fármacosRESUMEN
PURPOSE: To evaluate the capability of gels with low fluoride (F) concentration and supplemented with sodium trimetaphosphate (TMP) to promote in situ enamel remineralization. METHODS: Bovine enamel blocks were selected on the basis of their surface hardness after demineralization, and divided into five groups: gel without F or TMP (placebo); gel with 4,500 ppm F (4,500); gel with 4,500 ppm F + 5% TMP (4,500 5% TMP); gel with 9,000 ppm F (9,000) and gel with 12,300 ppm F (12,300). The study design was blind and cross-over: 12 subjects used palatal devices with four demineralized enamel blocks for 3 days, after topical fluoride application (TFA). Two blocks were removed immediately for analysis of the loosely bound fluoride (CaF2) and firmly bound fluoride (F) after TFA in enamel. In the remaining blocks, the percentage of surface hardness recovery (% SH), cross-sectional hardness (deltaKHN) and CaF2 and F were determined after remineralization. The results were subjected to ANOVA and Bonferroni tests (P < 0.05). RESULTS: The groups 4,500 5% TMP, 9,000, and 12,300 showed the best results with regard to % SH (P < 0.05). Lower deltaKHN values were observed in the 4,500 5% TMP and 12,300 gel groups (P < 0.05). Higher concentrations of CaF2 and F were observed in the 12,300 group, followed by the 4,500 5% TMP and 9,000 groups (P > 0.05). It was concluded that it is possible to promote enamel remineralization using gels with low fluoride concentration supplemented with TMP.
Asunto(s)
Cariostáticos/administración & dosificación , Esmalte Dental/efectos de los fármacos , Fluoruros/administración & dosificación , Polifosfatos/administración & dosificación , Remineralización Dental/métodos , Adulto , Animales , Biopsia , Fluoruro de Calcio/análisis , Cariostáticos/análisis , Bovinos , Estudios Cruzados , Esmalte Dental/química , Combinación de Medicamentos , Fluoruros/análisis , Fluoruros Tópicos/administración & dosificación , Geles , Dureza , Humanos , Microscopía de Polarización , Placebos , Método Simple Ciego , Desmineralización Dental/tratamiento farmacológico , Adulto JovenRESUMEN
This study evaluated the effect of Er,Cr:YSGG laser irradiation and professional fluoride application on enamel demineralization and on fluoride formation and retention. In a blind in vitro study, 264 human enamel slabs were distributed into 8 groups: G1--untreated; G2--treated with acidulated phosphate fluoride gel (APF gel, 1.23% F) for 4 min; G3, G4 and G5--irradiated with Er,Cr:YSGG at 2.8, 5.6 and 8.5 J/cm2, respectively; G6, G7 and G8--preirradiated with Er,Cr:YSGG at 2.8, 5.6 and 8.5 J/cm2, respectively, and subjected to APF gel application. Twenty slabs of each group were submitted to a pH-cycling regimen, and enamel demineralization was evaluated in 10 slabs of each group. In the other 10 slabs, CaF2-like material was determined. To evaluate F formed, 10 additional slabs of each group, not subjected to the pH cycling, were submitted to analysis of CaF2-like material and fluorapatite, while the other 3 slabs of each group were evaluated by scanning electron microscopy. The F content was also measured in all pH-cycling solutions. Laser at 8.5 J/cm2 and APF treatment reduced enamel demineralization compared to the control (p < 0.05), but the combination of these treatments was not more efficient than their isolated effect. A higher concentration of retained CaF2-like material was found in laser groups followed by APF in comparison with the APF gel treatment group. The findings suggest that laser treatment at 8.5 J/cm2 was able to decrease hardness loss, even though no additive effect with APF was observed. In addition, laser treatment increased the formation and retention of CaF2 on dental enamel.
Asunto(s)
Cariostáticos/uso terapéutico , Esmalte Dental/efectos de la radiación , Fluoruros/uso terapéutico , Láseres de Estado Sólido/uso terapéutico , Desmineralización Dental/prevención & control , Fluoruro de Fosfato Acidulado/análisis , Fluoruro de Fosfato Acidulado/uso terapéutico , Apatitas/análisis , Apatitas/efectos de la radiación , Fluoruro de Calcio/análisis , Fluoruro de Calcio/efectos de la radiación , Cariostáticos/análisis , Esmalte Dental/efectos de los fármacos , Esmalte Dental/ultraestructura , Fluoruros/análisis , Dureza , Humanos , Concentración de Iones de Hidrógeno , Electrodos de Iones Selectos , Microscopía Electrónica de Rastreo , Método Simple Ciego , Desmineralización Dental/metabolismo , Remineralización DentalRESUMEN
Although the effect of acidulated phosphate fluoride gel (APF gel) on caries reduction in permanent teeth is based on evidence, the relevance of the clinical application time is still under debate. Also, the effect of 4- versus 1-min application has not been evaluated in deciduous enamel. In a blind, crossover, in situ study of 14 days, 16 adult volunteers wore palatal appliances containing slabs of human permanent and deciduous enamel. At the beginning of each phase, the slabs were submitted to one of the following treatments: no APF application (negative control); APF gel (1.23% F) application for 1 or 4 min. Biofilm accumulation on the slab surface was allowed and the slabs were subjected eight times a day to 20% sucrose, simulating a high cariogenic challenge condition. On the 15th day of each phase, fluoride retained as CaF(2) and fluorapatite (FAp) was determined on the enamel of the slabs and demineralization was assessed by cross-sectional microhardness. Fluoride as CaF(2) and FAp, formed by APF gel application on the enamel slabs not subjected to the cariogenic challenge, was also determined. APF gel reduced demineralization in both enamel types (p < 0.05), but the difference between 1 and 4 min was not statistically significant (p > 0.05). CaF(2) and FAp formed and retained on deciduous and permanent enamel was significantly higher in APF gel groups (p < 0.05), but no significant difference was found between 1 and 4 min (p > 0.05). The findings suggest that 1 min of APF gel application provides a similar effect on inhibition of demineralization as 4 min, for both permanent and deciduous enamel.
Asunto(s)
Fluoruro de Fosfato Acidulado/uso terapéutico , Cariostáticos/uso terapéutico , Esmalte Dental/efectos de los fármacos , Fluoruros Tópicos/uso terapéutico , Desmineralización Dental/prevención & control , Diente Primario/efectos de los fármacos , Fluoruro de Fosfato Acidulado/administración & dosificación , Adolescente , Adulto , Apatitas/análisis , Apatitas/farmacocinética , Biopelículas/efectos de los fármacos , Fluoruro de Calcio/análisis , Fluoruro de Calcio/farmacocinética , Cariogénicos/farmacología , Cariostáticos/administración & dosificación , Estudios Cruzados , Esmalte Dental/metabolismo , Sacarosa en la Dieta/farmacología , Fluoruros Tópicos/administración & dosificación , Geles , Dureza , Humanos , Método Simple Ciego , Factores de Tiempo , Desmineralización Dental/metabolismo , Diente Primario/metabolismo , Adulto JovenRESUMEN
Because dentin is more caries-susceptible than enamel, its demineralization may be more influenced by additional fluoride (F). We hypothesized that a combination of professional F, applied as acidulated phosphate F (APF), and use of 1100-ppm-F dentifrice would provide additional protection for dentin compared with 1100-ppm-F alone. Twelve adult volunteers wore palatal appliances containing root dentin slabs, which were subjected, during 4 experimental phases of 7 days each, to biofilm accumulation and sucrose exposure 8x/day. The volunteers were randomly assigned to the following treatments: placebo dentifrice (PD), 1100-ppm-F dentifrice (FD), APF + PD, and APF+FD. APF gel (1.23% F) was applied to the slabs once at the beginning of the experimental phase, and the dentifrices were used 3x/day. APF and FD increased F concentration in biofilm fluid and reduced root dentin demineralization, presenting an additive effect. Analysis of the data suggests that the combination of APF gel application and daily regular use of 1100-ppm-F dentifrice may provide additional protection against root caries compared with the dentifrice alone.
Asunto(s)
Fluoruro de Fosfato Acidulado/uso terapéutico , Biopelículas/efectos de los fármacos , Cariostáticos/uso terapéutico , Dentífricos/uso terapéutico , Dentina/efectos de los fármacos , Fluoruros/uso terapéutico , Desmineralización Dental/prevención & control , Raíz del Diente/efectos de los fármacos , Fluoruro de Fosfato Acidulado/administración & dosificación , Adulto , Apatitas/análisis , Fluoruro de Calcio/análisis , Cariogénicos/efectos adversos , Cariostáticos/administración & dosificación , Estudios Cruzados , Placa Dental/microbiología , Dentífricos/administración & dosificación , Dentina/microbiología , Método Doble Ciego , Combinación de Medicamentos , Fluoruros/administración & dosificación , Geles , Dureza , Humanos , Microrradiografía , Placebos , Sacarosa/efectos adversos , Factores de Tiempo , Raíz del Diente/microbiología , Adulto JovenRESUMEN
Although the anticaries effect of fluoride (F) dentifrices is clearly established, the relative importance of F taken up by dental plaque not removed by brushing and of F products (CaF(2)-like) formed on totally cleaned enamel for the subsequent inhibition of demineralization is not known. Both effects were evaluated using conventional (1,100 microg F/g) and low-F concentration (500 microg F/g) dentifrices in a randomized, crossover, double-blind in situ study. Enamel blocks not treated or pretreated with the dentifrices to form CaF(2)-like deposits were mounted in palatal appliances in contact with a Streptococcus mutans test plaque. Volunteers brushed with non-F (negative control), low-F or conventional dentifrices and inserted the appliance in the mouth. F concentration in the fluid and solid phases of the test plaque was determined after 30 min, and a rinse with 20% sucrose solution was performed. After additional 45 min, plaque was collected and the loss of surface hardness at different test-plaque depths was measured. CaF(2)-like deposition on enamel and F taken up by plaque due to the use of F dentifrices were able to significantly increase F concentration in the fluid phase of the test plaque, but only the latter significantly reduced the loss of hardness because of the 20-30 times higher F concentration. Also, significant differences between the low-F and conventional dentifrices were observed for F on enamel, in plaque and on the subsequent loss of hardness. The results suggest that uptake of F by dental plaque not removed by brushing may be the main cause of the anticaries effect of F dentifrices.
Asunto(s)
Fluoruro de Calcio/administración & dosificación , Cariostáticos/administración & dosificación , Esmalte Dental/efectos de los fármacos , Dentífricos/uso terapéutico , Streptococcus mutans/metabolismo , Adulto , Análisis de Varianza , Fluoruro de Calcio/análisis , Fluoruro de Calcio/farmacocinética , Cariostáticos/farmacocinética , Estudios Cruzados , Placa Dental/química , Placa Dental/complicaciones , Placa Dental/microbiología , Placa Dental/prevención & control , Dentífricos/química , Dentífricos/farmacocinética , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Dureza/efectos de los fármacos , Humanos , Persona de Mediana Edad , Streptococcus mutans/efectos de los fármacos , Desmineralización Dental/etiología , Desmineralización Dental/microbiología , Desmineralización Dental/prevención & control , Diente Artificial , Adulto JovenRESUMEN
This blind and randomized study tested in vitro, using validated protocols, the anticaries potential of an experimental fluoride mouthrinse. One-hundred enamel slabs, half sound and half with caries-like lesions (carious), all with known surface microhardness (SMH), were submitted to 3 treatment groups: A) a placebo mouthrinse (negative control); B) a positive control mouthrinse containing 0.05% NaF; and C) an experimental formulation containing 0.05% NaF and cetylpyridinium chloride as an antibacterial substance. To evaluate the formation of F products on enamel, sound (n=10) and carious (n=10) slabs were treated with the formulations during 10 min and loosely and firmly-bound F formed in enamel were determined after extraction with alkali and acid, respectively. To evaluate the inhibition of enamel demineralization, sound enamel slabs (n=10) were treated with the mouthrinse formulations 2x/day during 1 min and subjected to a pH-cycling regimen simulating a cariogenic challenge (demineralization). To evaluate enamel remineralization, the carious slabs (n=10) were submitted to the treatments 3x/day and subjected to a pH-cycling model simulating a remineralizing condition. After 8 days, enamel SMH was determined again and the percentage of SMH loss or SMH recovery was calculated for the sound and carious slabs, respectively. The experimental formulation was superior to the negative control (p<0.05) and equivalent to the positive control (p>0.05) in the formation of F products in enamel, and in the inhibition of enamel demineralization and enhancement of remineralization. These data suggest that the tested experimental fluoride mouthrinse has anticaries potential.
Asunto(s)
Cariostáticos/uso terapéutico , Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Fluoruros/uso terapéutico , Antisépticos Bucales/uso terapéutico , Animales , Antibacterianos/uso terapéutico , Fluoruro de Calcio/análisis , Cariostáticos/análisis , Bovinos , Cetilpiridinio/uso terapéutico , Química Farmacéutica , Caries Dental/patología , Esmalte Dental/patología , Fluoruros/análisis , Dureza , Concentración de Iones de Hidrógeno , Placebos , Distribución Aleatoria , Método Simple Ciego , Fluoruro de Sodio/uso terapéutico , Factores de Tiempo , Remineralización DentalRESUMEN
The aim of this study was to develop a titanium tetrafluoride (TiF(4)) varnish and evaluate the stability of the formulation and its reactivity with dental enamel. The varnish was prepared in a resinous matrix using ethanol 96% as solvent. Samples (n=45) were aged at 65 degrees C and 30% of relativity humidity (RE n degrees 01/05-ANVISA) and after 3, 6, 9 and 12 months, nine samples were removed for evaluation and compared with fresh samples. Chemical stability of TiF(4) varnish was determinate by (19)F-NMR and the reactivity of the formulation was quantified by formation of fluoride loosely (CaF(2)) and firmly bound (fluorapatite; FA) to enamel. For reactivity comparisons, a varnish without TiF(4) was used as control. The loss of soluble fluoride was about 0.9% after one year of storage. The values of the reactivity (mean+/-S.D.) of fresh, aged at 3, 6, 9 and 12 months and control samples were: CaF(2) (microg F/mm(2)): 89.3+/-27.5(a); 54.5+/-14.3(b); 51.2+/-29.8(b); 69.3+/-21.3(a); 48.0+/-27.4(b); 0.10+/-0.07(c), FA (microg F/g): 2477.5+/-1044.0(a); 2484.8+/-992.0(a); 2580.0+/-1383.9(a); 2517.2+/-929.9(a); 2121.0+/-1059.2(a); 330.0+/-180.0(b), respectively. Means followed by distinct letters were statistically different (p<0.05). After one year of storage, the formulation was chemically stable and the levels of FA were maintained. However there was an initial decrease in the ability to form CaF(2).
Asunto(s)
Fluoruro de Calcio/análisis , Cariostáticos/uso terapéutico , Fluoruros Tópicos/uso terapéutico , Fluoruros/síntesis química , Esmalte Dental/efectos de los fármacos , Fluoruros/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Titanio/metabolismoRESUMEN
This blind and randomized study tested in vitro, using validated protocols, the anticaries potential of an experimental fluoride mouthrinse. One-hundred enamel slabs, half sound and half with caries-like lesions (carious), all with known surface microhardness (SMH), were submitted to 3 treatment groups: A) a placebo mouthrinse (negative control); B) a positive control mouthrinse containing 0.05 percent NaF; and C) an experimental formulation containing 0.05 percent NaF and cetylpyridinium chloride as an antibacterial substance. To evaluate the formation of F products on enamel, sound (n=10) and carious (n=10) slabs were treated with the formulations during 10 min and loosely and firmly-bound F formed in enamel were determined after extraction with alkali and acid, respectively. To evaluate the inhibition of enamel demineralization, sound enamel slabs (n=10) were treated with the mouthrinse formulations 2x/day during 1 min and subjected to a pH-cycling regimen simulating a cariogenic challenge (demineralization). To evaluate enamel remineralization, the carious slabs (n=10) were submitted to the treatments 3x/day and subjected to a pH-cycling model simulating a remineralizing condition. After 8 days, enamel SMH was determined again and the percentage of SMH loss or SMH recovery was calculated for the sound and carious slabs, respectively. The experimental formulation was superior to the negative control (p<0.05) and equivalent to the positive control (p>0.05) in the formation of F products in enamel, and in the inhibition of enamel demineralization and enhancement of remineralization. These data suggest that the tested experimental fluoride mouthrinse has anticaries potential.
Este estudo in vitro, cego e randomizado avaliou o potencial anticárie de uma formulação experimental de enxaguatório fluoretado (F), usando protocolos previamente validados. Blocos de esmalte (120), 60 hígidos e 60 com lesão artificial de cárie, com microdureza de superfície (MDS) conhecida, foram submetidos a 3 grupos de tratamentos: A) Enxaguatório placebo (controle negativo); B) Controle positivo contendo NaF 0,05 por cento e C) Uma formulação experimental contendo NaF 0,05 por cento e cloreto de cloreto de cetil-piridínio como antibacteriano. Para testar a capacidade de formação de produtos fluoretados no esmalte, blocos hígidos (n=10) e cariados (n=10) foram tratados durante 10 min e os fluoretos fracamente e fortemente ligados formados foram determinados após extração com álcali e ácido, respectivamente. Para avaliar a inibição da desmineralização do esmalte, os blocos hígidos (n=10) foram tratados com as formulações 2 x/dia durante 1 min e submetidos a um modelo de ciclagem de pH, simulando o processo de desmineralização. Para avaliar a ativação da remineralização do esmalte, os blocos com lesões de cárie (n=10) foram tratados 3 x/dia e submetidos a um modelo de ciclagens de pH, simulando uma condição de remineralização. Após 8 dias, a MDS do esmalte foi novamente determinada e as porcentagens de sua redução ou aumento foram calculadas, respectivamente para os blocos hígidos ou com lesão de cárie. A formulação experimental foi superior ao controle negativo (p<0,05) e equivalente ao positivo (p>0,05), na formação de produtos fluoretados no esmalte e na inibição de sua desmineralização e ativação da remineralização. Conclui-se que o enxaguatório experimental apresenta fluoreto ativo com potencial para controlar cárie dental.
Asunto(s)
Animales , Bovinos , Cariostáticos/uso terapéutico , Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Fluoruros/uso terapéutico , Antisépticos Bucales/uso terapéutico , Antibacterianos/uso terapéutico , Química Farmacéutica , Fluoruro de Calcio/análisis , Cariostáticos/análisis , Cetilpiridinio/uso terapéutico , Caries Dental/patología , Esmalte Dental/patología , Fluoruros/análisis , Dureza , Concentración de Iones de Hidrógeno , Placebos , Distribución Aleatoria , Método Simple Ciego , Fluoruro de Sodio/uso terapéutico , Factores de Tiempo , Remineralización DentalRESUMEN
Galvanic sludge is classified as a hazardous waste and incineration is one of the techniques used for its treatment. The aim of this work is to study the thermal behavior of a galvanic sludge which contains only chromium as a restriction metal. Simultaneous DTA/TG coupled with mass spectrometer tests were performed to characterize the thermal behavior of the sludge. Besides thermal analysis, sludge samples were heated in a specially designed furnace and these samples were submitted to X-ray diffraction. Vapor from the heated sludge was condensed and the particles were analyzed by EDS microprobe coupled in a scanning electron microscope. The slag formed after the calcination of the galvanic sludge was mainly composed of a mixture of calcium phosphate and fluoride. and minor concentrations of metals. A total weight loss of 34% was observed. The greatest part of this weight loss corresponds to CO2, H2O and SO2. H2O is liberated in the temperature range of 500-1,250 degrees C. CO2 in the range of 500-750 degrees C and SO2 near 1,000 degrees C. Chromium evaporation was not observed in relevant quantities, about 99.6% of the Cr remained incorporated in the slag.
Asunto(s)
Cromo/química , Galvanoplastia , Residuos Peligrosos/análisis , Calor , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/química , Fluoruro de Calcio/análisis , Fosfatos de Calcio/análisis , Dióxido de Carbono/análisis , Cromo/análisis , Incineración , Residuos Industriales/análisis , Microscopía Electrónica de Rastreo , Análisis Espectral , Dióxido de Azufre/análisis , Difracción de Rayos XRESUMEN
The aim of this study was to quantify, in vitro, the formation of CaF2 after the application of three fluoridated gels: one neutral, one acidulated and another highly acidulated, on a bovine enamel dental surface treated with a Dijkman's demineralizing solution (1990). 145 sections were utilized, obtained from 145 sound teeth and divided into seven groups: C (enamel without treatment); FN1 (enamel demineralized and treated with neutral gel for 1 minute); FN4 (enamel demineralized and treated with neutral gel for 4 minutes); FFA1 (enamel demineralized and treated with acidulated gel for 1 minute); FFA4 (enamel demineralized and treated with acidulated gel for 4 minutes); FAA1 (enamel demineralized and treated with highly acidulated gel for 1 minute) and FAA4 (enamel demineralized and treated with highly acidulated gel for 4 minutes). The formation of CaF2 was analyzed by SEM and chemically by Caslavska's method (1975). The average and standard deviations from the groups studied were respectively: C-0.63; 0.38; FN1-23.06; 16.52; FFA1-54.11; 49.00; FAA1-43.87; 32.66; FN4-34.92; 23.00; FFA4-67.91; 42.36; FAA4-56.03; 38.96. (Mann-Whitney non-parametric test). The time of application did not interfere in the CaF2 formation from the acidulated and highly-acidulated gels. A minor concentration of fluoride and amount of pH from highly-acidulated gel did not affect the higher formation from the CaF2 in relation to the acidulated gel in both cases when the application was evaluated.
Asunto(s)
Fluoruro de Calcio/análisis , Fluoruros Tópicos/química , Fluoruro de Fosfato Acidulado/administración & dosificación , Fluoruro de Fosfato Acidulado/química , Animales , Bovinos , Esmalte Dental , Fluoruros Tópicos/administración & dosificación , Geles , Humanos , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Fluoruro de Sodio/administración & dosificación , Fluoruro de Sodio/química , Estadísticas no Paramétricas , Factores de TiempoRESUMEN
The possibility of having a commercial product such as waxed floss with an additional agent for controlling and preventing caries is promising. The aim of this research was to determine the uptake of fluoride on tooth enamel in situ after the utilization of a dental floss with fluoride incorporated into the wax. One hundred blocks of bovine enamel were artificially demineralized and randomly separated into a Control Group (C) and a Test Group (T). The dental blocks in group T were mounted two-by-two simulating proximal contacts and were fixed into intra-oral lower arch devices. Eight volunteers with a similar salivary flow and buffer capacity wore devices with the enamel blocks for eight days. During this period of time the subjects applied a 25 cm long portion of a mint waxed floss with fluoride (0.15 mgF/m, Oral-B) between the blocks, 3 times a day for 2 minutes after each meal. At the same time, brushing was carried out with a fluoride-free toothpaste. The alkali-soluble fluoride (CaF2) formed on the enamel was extracted using the Caslavska et al. method and measured with the Orion 96-09 electrode-specific and the EA 720 ion analyzer. The results showed that the group that had the most CaF2 on the enamel (median, minimum and maximum in microF/cm2) was Group T (3.00, 2.11 and 4.00), which differed significantly (p < 0.01) from group C (0.26, 0.10 and 0.69). It was concluded that fluoride uptake on enamel was 11.54 times higher after use of dental floss with fluoride in this study.
Asunto(s)
Dispositivos para el Autocuidado Bucal , Fluoruros/farmacocinética , Adulto , Animales , Fluoruro de Calcio/análisis , Fluoruro de Calcio/metabolismo , Bovinos , Esmalte Dental/química , Esmalte Dental/metabolismo , Femenino , Fluoruros/administración & dosificación , Humanos , Técnicas In Vitro , Masculino , Distribución Aleatoria , CerasRESUMEN
Os autores, através de uma metodologia in vitro, avaliam 2 tempos de aplicaçäo de gel flúor-fosfato acidulado (FFA), 1 e 4 min, em esmalte dental humano hígido. Realizaram análise de fluoreto de cálcio (flúor fracamente ligado ao esmalte) e fluoratita (flúor fortemente ligado ao esmalte). Encontraram, através do teste näo paramétrico de Kruskall-Wallis H, considerando nível de significância de 1 por cento, diferença significante entre o grupo controle e os grupos testes. Näo encontraram diferença significante entre os dois grupos testes
Asunto(s)
Esmalte Dental/efectos de los fármacos , Fluoruro de Calcio/análisis , Fluoruro de Calcio/efectos adversos , Fluoruro de Calcio/uso terapéutico , Técnicas In Vitro , Factores de Tiempo , Geles/análisis , Geles/efectos adversos , Geles/uso terapéuticoRESUMEN
Enamel specimens from unerupted third molars were treated with the supernatant of monofluorophosphate (MFP)-containing toothpaste slurries in water. Calcium fluoride-like particles were formed on the enamel surface during a 24-h exposure. The globules were soluble in alkali. More particles were seen on enamel treated with a toothpaste containing both MFP and NaF. The experiments showed that the calcium fluoride-like material formed on enamel after treatment with MFP-containing toothpaste probably originates from the free fluoride present in the pastes. The relatively moderate deposition of fluoride may be of clinical significance because the teeth are so frequently exposed to toothpaste. No firmly bound fluoride was found on treatment of enamel with MFP-containing toothpaste.
Asunto(s)
Fluoruro de Calcio/farmacocinética , Esmalte Dental/metabolismo , Fluoruros/administración & dosificación , Fluoruros/farmacocinética , Fosfatos/administración & dosificación , Pastas de Dientes , Adsorción , Fluoruro de Calcio/análisis , Fluoruro de Calcio/química , Esmalte Dental/química , Esmalte Dental/ultraestructura , Fluoruros/análisis , Fluoruros/química , Humanos , Hidróxidos , Microscopía Electrónica de Rastreo , Fosfatos/química , Compuestos de Potasio , Fluoruro de Sodio/administración & dosificación , SolubilidadRESUMEN
The first aim of the present study was to examine if alkali-soluble fluoride (calcium fluoride-like material and adsorbed fluoride) forms when a NaF-containing toothpaste is applied on human enamel surface in vitro. The centrifuged supernatants of toothpastes dissolved in distilled water were used and four different commercial NaF-containing toothpastes were tested. The second aim was to investigate if pyrophosphate would interfere with the deposition of alkali soluble fluoride. The formation of alkali-soluble fluoride was determined by chemical analysis and visualized by scanning electron microscopy (SEM). It was ascertained that all tested toothpastes contained free fluoride according to the manufacturers' specifications. It was shown that they promoted deposition of alkali soluble fluoride on the enamel surface. The amount of deposited material increased with the time of exposure. The clinical effect of a NaF-containing toothpaste may thus well depend on an initial formation of alkali-soluble fluoride. Fluoride from this reservoir may adsorb onto the enamel crystals and inhibit further demineralization or increase the rate of remineralization during cariogenic challenges. It was also demonstrated that pyrophosphate did not interfere with the deposition of alkali soluble fluoride.
Asunto(s)
Fluoruro de Calcio/química , Esmalte Dental/ultraestructura , Difosfatos/química , Fluoruros/química , Fluoruro de Sodio/química , Pastas de Dientes , Adsorción , Álcalis , Fluoruro de Calcio/análisis , Esmalte Dental/química , Electroquímica , Fluoruros/análisis , Humanos , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , SolubilidadRESUMEN
The aim of this study was to quantify the formation of alkali-soluble fluoride (loosely bound fluoride such as calcium fluoride-like material and absorbed fluoride) and alkali-insoluble fluoride (firmly bound fluoride or apatitically bound fluoride) when fluoride mouthrinsing solutions were applied on sound human enamel in vitro. Two commercial products containing 0.2% or 0.05% NaF were used during 30 sec, 60 sec, 5 min, and 60 min. The formation of loosely bound fluoride was determined by KOH extraction and visualized by scanning electron microscopy. The firmly bound fluoride was measured by three consecutive acid etchings of the enamel. Even during short periods of application there were deposits on the enamel surface. The amount of deposit increased with time of exposure to the 0.2% NaF solution. Only after treatment for 60 min with 0.05% NaF were significant amounts of alkali-soluble fluoride deposited. No measurable amounts of firmly bound fluoride were observed.