ABSTRACT
Abstract: The aim of this study was to evaluate soluble and insoluble fluoride concentrations in commercial varnishes, and their remineralization effect on artificial caries enamel lesions using surface and cross-sectional microhardness evaluations. Forty bovine enamel blocks were separated into four groups (n=10): control (no treatment), Enamelast (Ultradent Products), Duraphat (Colgate-Palmolive) and Clinpro White Varnish (3M ESPE). Surface enamel microhardness evaluations were obtained, artificial enamel caries lesions were developed by dynamic pH-cycling, and the varnishes were then applied every 6 days, after which the enamel blocks were submitted to dynamic remineralization by pH cycles. After removal of the varnishes, the enamel surfaces were reassessed for microhardness. The blocks were sectioned longitudinally, and cross-sectional microhardness measurements were performed at different surface depths (up to 300 μm depth). Polarized light microscopy images (PLMI) were made to analyze subsurface caries lesions. The fluoride concentration in whole (soluble and insoluble fluoride) and centrifuged (soluble fluoride) varnishes was determined using an extraction method with acetone. The data were analyzed to evaluate the surface microhardness, making adjustments for generalized linear models. There was a significant decrease in enamel surface microhardness after performing all the treatments (p<0.0001). Enamelast and Duraphat showed significantly higher enamel microhardness values than the control and the Clinpro groups (p = 0.0002). Microhardness loss percentage was significantly lower for Enamelast (p = 0.071; One-way ANOVA). PLMI showed that subsurface caries lesions were not remineralized with the varnish treatments. No significant differences in the in-depth microhardness levels (p = 0.7536; ANOVA) were observed among the treatments. Enamelast presented higher soluble and insoluble fluoride concentrations than the other varnishes (p < 0.0001; Kruskal-Wallis and Dunn tests). Enamelast and Duraphat varnishes promoted enamel surface remineralization, but no varnish remineralized the subsurface lesion body. Although insoluble and soluble fluoride concentration values did not correspond to those declared by the manufacturer, Enamelast presented higher fluoride concentration than the others.
Subject(s)
Animals , Cattle , Tooth Remineralization/methods , Cariostatic Agents/chemistry , Fluorides, Topical/chemistry , Dental Caries/drug therapy , Dental Enamel/drug effects , Reference Values , Surface Properties/drug effects , Time Factors , Materials Testing , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Hardness Tests , Microscopy, PolarizationABSTRACT
Abstract We assessed the effect of a new coating material based on resin-modified glass-ionomer with calcium (Ca) in inhibiting the demineralization of underlying and adjacent areas surrounding caries-like lesions in enamel. The measures used were surface hardness (SH) and cross-sectional hardness (CSH). Thirty-six bovine enamel specimens (3 × 6 × 2 mm) were randomly allocated into three groups (n = 12): No treatment (NT); resin-modified glass-ionomer with Ca (Clinpro XT Varnish, 3M ESPE) (CL), and fluoride varnish (Duraphat, Colgate) (DU). The specimens were subjected to alternated immersions in demineralizing (6 h) and remineralizing solutions (18 h) for 7 days. SH measurements were conducted at standard distances of 150, 300, and 450 µm from the treatment area. CSH evaluated the mean hardness profile over the depth of the enamel surface and at standard distances from the materials. The energy-dispersive X-ray spectroscopy analysis was conducted to evaluate the demineralization bands created on the sublayer by % of calcium (Ca), phosphorus (P), and fluoride (F). Ca/P weight ratio was also calculated. Based on SH and CSH measurements, there was no difference between groups at the distances 150 µm (p = 0.882), 300 µm (p = 0.995), and 450 µm (p = 0.998). Up to 50 µm depth (at 150 µm from the treatment area), CL showed better performance than DU ( p< 0.05). NT presented higher loss of Ca and P than CL and DU (p < 0.05). There was no significant difference in the % of F ion among the three groups. The new coating material was similar to F varnish in attenuating enamel demineralization.
Subject(s)
Animals , Cattle , Calcium/chemistry , Resin Cements/chemistry , Dental Enamel/drug effects , Glass Ionomer Cements/chemistry , Reference Values , Sodium Fluoride/chemistry , Spectrometry, X-Ray Emission , Surface Properties/drug effects , Time Factors , Materials Testing , Cariostatic Agents/chemistry , Random Allocation , Fluorides, Topical/chemistry , Reproducibility of Results , Tooth Demineralization/prevention & control , Hardness Tests , Hydrogen-Ion ConcentrationABSTRACT
Abstract Radiation-related caries are one the most undesired reactions manifested during or after head and neck radiotherapy. Fluoride application is an important strategy to reduce demineralization and enhance remineralizaton. Objective: To evaluate the effect of the topical application of fluoride during irradiation on dental enamel demineralization. Material and Methods: Thirty molars were randomly divided into three groups: Non-irradiated (NI), Irradiated (I), Irradiated with fluoride (IF). Each group was subdivided according to the presence or absence of pH-cycling (n=5). In the irradiated groups, the teeth received 70 Gy. The enamel's chemical composition was measured using Fourier Transform Infrared Spectrometry (organic matrix/mineral ratio - M/M and relative carbonate content - RCC). Vickers microhardness (VHN) and elastic modulus (E) were evaluated at three depths (surface, middle and deep enamel). Scanning electron microscopy (SEM) was used to assess the enamel's morphology. Results: The FTIR analysis (M/M and RCC) showed significant differences for irradiation, pH-cycling and the interaction between factors (p<0.001). Without pH-cycling, IF had the lowest organic matrix/mineral ratio and relative carbonate content. With pH-cycling, the organic matrix/mineral ratio increased and the relative carbonate content decreased, except for IF. VHN was influenced only by pH-cycling (p<0.001), which generated higher VHN values. ANOVA detected significant differences in E for irradiation (p<0.001), pH-cycling (p<0.001) and for the interaction between irradiation and pH-cycling (p<0.001). Increased E was found for group I without pH-cycling. With pH-cycling, groups I and IF were similar, and showed higher values than NI. The SEM images showed no morphological changes without pH-cycling. With pH-cycling, fluoride helped to maintain the outer enamel's morphology. Conclusions: Fluoride reduced mineral loss and maintained the outer morphology of irradiated and cycled enamel. However, it was not as effective in preserving the mechanical properties of enamel. Radiotherapy altered the enamel's elastic modulus and its chemical composition.
Subject(s)
Humans , Cariostatic Agents/pharmacology , Fluorides, Topical/pharmacology , Tooth Demineralization/prevention & control , Dental Enamel/drug effects , Radiotherapy/adverse effects , Reference Values , Surface Properties , Microscopy, Electron, Scanning , Cariostatic Agents/radiation effects , Cariostatic Agents/chemistry , Random Allocation , Fluorides, Topical/radiation effects , Fluorides, Topical/chemistry , Reproducibility of Results , Analysis of Variance , Tooth Demineralization/etiology , Spectroscopy, Fourier Transform Infrared , Dental Enamel/radiation effects , Elastic Modulus , Hardness Tests , Hydrogen-Ion ConcentrationABSTRACT
ABSTRACT Objective The aim of this study was to evaluate the efficacy of CPP-ACP containing fluoride varnish for remineralizing white spot lesions (WSLs) with four different quantitative methods. Material and Methods Four windows (3x3 mm) were created on the enamel surfaces of bovine incisor teeth. A control window was covered with nail varnish, and WSLs were created on the other windows (after demineralization, first week and fourth week) in acidified gel system. The test material (MI Varnish) was applied on the demineralized areas, and the treated enamel samples were stored in artificial saliva. At the fourth week, the enamel surfaces were tested by surface microhardness (SMH), quantitative light-induced fluorescence-digital (QLF-D), energy-dispersive spectroscopy (EDS) and laser fluorescence (LF pen). The data were statistically analyzed (α=0.05). Results While the LF pen measurements showed significant differences at baseline, after demineralization, and after the one-week remineralization period (p<0.05), the difference between the 1- and 4-week was not significant (p>0.05). With regards to the SMH and QLF-D analyses, statistically significant differences were found among all the phases (p<0.05). After the 1- and 4-week treatment periods, the calcium (Ca) and phosphate (P) concentrations and Ca/P ratio were higher compared to those of the demineralization surfaces (p<0.05). Conclusion CPP-ACP containing fluoride varnish provides remineralization of WSLs after a single application and seems suitable for clinical use.
Subject(s)
Animals , Cattle , Tooth Remineralization/methods , Cariostatic Agents/chemistry , Caseins/chemistry , Fluorides, Topical/chemistry , Dental Enamel/drug effects , Reference Values , Saliva, Artificial/chemistry , Spectrometry, X-Ray Emission , Surface Properties , Time Factors , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Tooth Demineralization/drug therapy , Fluorescence , Hardness TestsABSTRACT
Objective This in vitro study assessed the anti-erosive effect of experimental mouthrinses containing TiF4 and NaF on dentin erosive loss.Material and Methods Bovine dentin specimens were randomly allocated into the groups (n=15): 1) SnCl2/NaF/AmF (Erosion Protection®/GABA, pH 4.5, positive control); 2) experimental solution with 0.0815% TiF4(pH 2.5); 3) 0.105% NaF (pH 4.5); 4) 0.042% NaF+0.049% TiF4 (pH 4.4); 5) 0.063% NaF+0.036% TiF4 (pH 4.5); 6) no treatment (negative control). Each specimen was cyclically demineralized (Sprite Zero, pH 2.6, 4x90 s/day) and exposed to artificial saliva between the erosive challenges for 7 days. The treatment with the fluoride solutions was done 2x60 s/day, immediately after the first and the last erosive challenges of the day. Dentin erosive loss was measured by profilometry (μm). The data were analyzed using Kruskal Wallis/Dunn tests (p<0.05).Results Mouthrinses containing TiF4or Sn/F were able to show some protective effect against dentin erosive loss compared to negative control. The best anti-erosive effect was found for experimental solution containing 0.0815% TiF4 (100% reduction in dentin loss), followed by 0.042% NaF+0.049% TiF4 (58.3%), SnCl2/NaF/AmF (52%) and 0.063% NaF+0.036% TiF4 (40%). NaF solution (13.3%) did not significantly differ from control.Conclusion The daily application of experimental mouthrinse containing TiF4and NaF has the ability to reduce dentin erosion, as well as Erosion Protection® and TiF4 alone.
Subject(s)
Animals , Cattle , Cariostatic Agents/chemistry , Dentin/drug effects , Fluorides/chemistry , Mouthwashes/chemistry , Sodium Fluoride/chemistry , Titanium/chemistry , Tooth Erosion/prevention & control , Carbonated Beverages , Fluorides, Topical/chemistry , Hydrogen-Ion Concentration , Random Allocation , Reproducibility of Results , Surface Properties , Time FactorsABSTRACT
Este estudo teve como o objetivo avaliar in vitro o efeito do tratamento com vernizes de tetrafluoreto de titânio (TiF4) e fluoreto de sódio (NaF) (ambos com 0,95%, 1,95% e 2,45% F) sobre 1) a quantidade de F- liberada em água deionizada e saliva artificial, por período de 12h; 2) os tipos de compostos formados pela interação com a hidroxiapatita (neste caso, com soluções ao invés dos vernizes); 3) a porcentagem de elementos presentes na superfície do esmalte bovino e humano, hígidos (H) e desmineralizados (DES); 4) a quantidade de CaF2 sobre a superfície do esmalte bovino e humano, H e DES. Adicionalmente, 5) o efeito dos vernizes de TiF4 e NaF sobre a remineralização do esmalte bovino, em diferentes condições in situ, foi avaliado. Para etapa 1, a liberação de F- foi quantificada por eletrodo de íon específico. Na etapa 2, pó de HAP produzido por precipitação foi tratado com soluções fluoretadas. Os compostos formados foram avaliados por espectroscopia de infravermelho e difração de raios-X. Nas etapas 3 e 4, as superfícies tratadas com os vernizes foram analisadas por MEV- EDAX e por biópsias básicas, respectivamente. Vinte voluntários (n final=17) participaram do ensaio in situ com 3 fases cruzadas, os quais utilizaram aparelhos palatinos contendo amostras de esmalte bovino desmineralizadas tratadas com vernizes de TiF4, NaF ou placebo. As amostras foram submetidas a diferentes condições de des-remineralização (presença ou não de tela plástica; variação da frequência de aplicação de sacarose 20%) e à exposição ao dentifrício fluoretado. O volume mineral e profundidade da lesão foram avaliados por microradiografia transversal (TMR). 1) Os vernizes de TiF4 (1,95 e 2,45% F) liberaram mais fluoreto comparados aos vernizes de NaF tanto em água como em saliva artificial, sendo a diferença significativa nas primeiras 6h de contato (p<0,0001). 2) O TiF4 causou alteração na estrutura da HAP e induziu à formação de novos compostos como TiO2 e Ti (HPO4)2. 3)...
This study aimed to evaluate the in vitro effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) varnishes (both with 0.95%, 1.95%, 2.45% F) treatment on the 1) F- release in deionized water and artificial saliva for 12h period; 2) types of compounds formed by the interaction with hydroxyapatite (in this case, solutions were tested instead of varnishes); 3) percentage of the elements on bovine and human, sound (S) and demineralized (DE), enamel surface; 4) F- uptake (CaF2 deposition) on human and bovine, S and DE, enamel surface. Additionally, 5) the effect of TiF4 and NaF varnishes on bovine enamel remineralization, in different in situ conditions, was assessed. In study 1, the F- release was measured by ion specific electrode. In study 2, HAP powder, produced by precipitation, was treated with fluoride solutions. The compounds formed were evaluated by infrared spectroscopy and X-ray diffraction. In studies 3 and 4, the surfaces treated with the varnishes were analyzed by SEM-EDAX and basic biopsies, respectively. Twenty volunteers (final n=17) participated of the in situ study with 3 crossover phases, in which they wore palatal appliances containing bovine demineralized enamel samples treated with TiF4, NaF or placebo varnishes. The samples were subjected to different de-remineralization conditions (presence or absence of plastic mesh and variation in frequency of application of 20% sucrose) and exposure to fluoride dentifrice. Themineral content and lesion depth were evaluated by transverse microradiography (TMR). 1) The TiF4 varnishes (1.95 and 2.45% F) released more F- compared to NaF varnishes in both water and artificial saliva, and significant difference was found in the first 6h (p<0.0001). 2) The TiF4 caused change in the HAP structure and induced the formation of new compounds such as TiO2 and Ti (HPO4)2. 3) The TiF4 varnishes induced the formation of a coating layer rich in Ti and F, with microcracks in its extension, on the enamel...
Subject(s)
Humans , Animals , Cattle , Dental Caries/prevention & control , Tooth Demineralization/prevention & control , Dental Enamel , Fluorides, Topical/chemistry , Hydroxyapatites/chemistry , Titanium/chemistry , Cariostatic Agents/chemistry , Sodium Fluoride/chemistry , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Saliva, Artificial/chemistryABSTRACT
Este estudo teve como o objetivo avaliar in vitro o efeito do tratamento com vernizes de tetrafluoreto de titânio (TiF4) e fluoreto de sódio (NaF) (ambos com 0,95%, 1,95% e 2,45% F) sobre 1) a quantidade de F- liberada em água deionizada e saliva artificial, por período de 12h; 2) os tipos de compostos formados pela interação com a hidroxiapatita (neste caso, com soluções ao invés dos vernizes); 3) a porcentagem de elementos presentes na superfície do esmalte bovino e humano, hígidos (H) e desmineralizados (DES); 4) a quantidade de CaF2 sobre a superfície do esmalte bovino e humano, H e DES. Adicionalmente, 5) o efeito dos vernizes de TiF4 e NaF sobre a remineralização do esmalte bovino, em diferentes condições in situ, foi avaliado. Para etapa 1, a liberação de F- foi quantificada por eletrodo de íon específico. Na etapa 2, pó de HAP produzido por precipitação foi tratado com soluções fluoretadas. Os compostos formados foram avaliados por espectroscopia de infravermelho e difração de raios-X. Nas etapas 3 e 4, as superfícies tratadas com os vernizes foram analisadas por MEV- EDAX e por biópsias básicas, respectivamente. Vinte voluntários (n final=17) participaram do ensaio in situ com 3 fases cruzadas, os quais utilizaram aparelhos palatinos contendo amostras de esmalte bovino desmineralizadas tratadas com vernizes de TiF4, NaF ou placebo. As amostras foram submetidas a diferentes condições de des-remineralização (presença ou não de tela plástica; variação da frequência de aplicação de sacarose 20%) e à exposição ao dentifrício fluoretado. O volume mineral e profundidade da lesão foram avaliados por microradiografia transversal (TMR). 1) Os vernizes de TiF4 (1,95 e 2,45% F) liberaram mais fluoreto comparados aos vernizes de NaF tanto em água como em saliva artificial, sendo a diferença significativa nas primeiras 6h de contato (p<0,0001). 2) O TiF4 causou alteração na estrutura da HAP e induziu à formação de novos compostos como TiO2 e Ti (HPO4)2. 3)...
This study aimed to evaluate the in vitro effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) varnishes (both with 0.95%, 1.95%, 2.45% F) treatment on the 1) F- release in deionized water and artificial saliva for 12h period; 2) types of compounds formed by the interaction with hydroxyapatite (in this case, solutions were tested instead of varnishes); 3) percentage of the elements on bovine and human, sound (S) and demineralized (DE), enamel surface; 4) F- uptake (CaF2 deposition) on human and bovine, S and DE, enamel surface. Additionally, 5) the effect of TiF4 and NaF varnishes on bovine enamel remineralization, in different in situ conditions, was assessed. In study 1, the F- release was measured by ion specific electrode. In study 2, HAP powder, produced by precipitation, was treated with fluoride solutions. The compounds formed were evaluated by infrared spectroscopy and X-ray diffraction. In studies 3 and 4, the surfaces treated with the varnishes were analyzed by SEM-EDAX and basic biopsies, respectively. Twenty volunteers (final n=17) participated of the in situ study with 3 crossover phases, in which they wore palatal appliances containing bovine demineralized enamel samples treated with TiF4, NaF or placebo varnishes. The samples were subjected to different de-remineralization conditions (presence or absence of plastic mesh and variation in frequency of application of 20% sucrose) and exposure to fluoride dentifrice. Themineral content and lesion depth were evaluated by transverse microradiography (TMR). 1) The TiF4 varnishes (1.95 and 2.45% F) released more F- compared to NaF varnishes in both water and artificial saliva, and significant difference was found in the first 6h (p<0.0001). 2) The TiF4 caused change in the HAP structure and induced the formation of new compounds such as TiO2 and Ti (HPO4)2. 3) The TiF4 varnishes induced the formation of a coating layer rich in Ti and F, with microcracks in its extension, on the enamel...
Subject(s)
Humans , Animals , Cattle , Dental Caries/prevention & control , Tooth Demineralization/prevention & control , Dental Enamel , Fluorides, Topical/chemistry , Hydroxyapatites/chemistry , Titanium/chemistry , Cariostatic Agents/chemistry , Sodium Fluoride/chemistry , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Saliva, Artificial/chemistryABSTRACT
The aim of this study was to analyze fluoride stability in dentifrices stored during nine months in schools from Careiro da Várzea, State of Amazonas, Brazil. Analysis of total fluoride concentration, total soluble fluoride, and ionic fluoride in the dentifrice samples was performed in four different time periods: at the time of purchase (baseline); after three months, after six months, and after nine months of storage. Fluoride concentration was determined using a specific electrode (Orion 96-09) connected to an ion analyzer (Orion A-720) and calibrated with fluoride standard solutions containing 2.0 to 32.0 ppm F. The results obtained during the measurements were analyzed by analysis of variance (one-way ANOVA), followed by Tukey’s test for comparison of the means. After nine months of storage, total soluble fluoride, the active form of fluoride, decreased by 21.9%. As total soluble fluoride was below the minimum required for anticaries efficacy (1,000 ppm F) in the fourth analysis, it may be concluded that anticaries potential decreased with storage time.
Subject(s)
Cariostatic Agents/chemistry , Drug Storage/standards , Fluorides, Topical/chemistry , Toothpastes/chemistry , Analysis of Variance , Brazil , Cariostatic Agents/analysis , Drug Stability , Dental Caries/prevention & control , Fluorides, Topical/analysis , Prospective Studies , Schools , Statistics, Nonparametric , Temperature , Time FactorsABSTRACT
The aims of this study were (1) to assess the amount of fluoride (F) released from varnishes containing calcium glycerophosphate (CaGP) and (2) to assess the effect of the experimental varnishes on in vitrodemineralization. Six test groups using 5 varnishes: base varnish (no active ingredients); Duraphat® (2.26% NaF); Duofluorid® (5.63% NaF/CaF2); experimental varnish 1 (1% CaGP/5.63% NaF/CaF2); experimental varnish 2 (5% CaGP/5.63% NaF/CaF2); and no varnish were set up. In stage 1, 60 acrylic blocks were randomly distributed into 6 groups (n = 10). Then 300 µg of each varnish was applied to each block. The blocks were immersed in deionized water, which was changed after 1, 8, 12, 24, 48 and 72 hours. Fluoride concentration in the water was analyzed using a fluoride electrode. In stage 2, 60 bovine enamel samples were distributed into 6 groups (n = 10), and treated with 300 µg of the respective varnish. After 6 h the varnish was removed and the samples were subjected to a 7-day in vitro pH cycle (6 h demineralization/18 h remineralization per day). The demineralization was measured using surface hardness. The results showed that both experimental varnishes released more fluoride than Duofluorid® and Duraphat® (p < 0.05), but Duraphat® showed the best preventive effect by decreasing enamel hardness loss (p < 0.05). Therefore, we conclude that even though (1) the experimental varnishes containing CaGP released greater amounts of F, (2) they did not increase in the preventive effect against enamel demineralization.
Subject(s)
Animals , Cattle , Cariostatic Agents/chemistry , Dental Enamel/drug effects , Fluorides, Topical/chemistry , Glycerophosphates/chemistry , Sodium Fluoride/chemistry , Tooth Demineralization/prevention & control , Dental Caries/prevention & control , Hardness Tests , Materials Testing , Random Allocation , Reference Values , Reproducibility of Results , Surface Properties , Time Factors , Water/chemistryABSTRACT
Objetivo. Establecer las concentraciones de plomo (Pb) en sangre en niños escolares de 1998 y 2008, así como su asociación con factores de riesgo. Material y métodos. Se llevó a cabo un monitoreo de Pb en sangre de niños de entre 6 y 12 años que cursan educación primaria en 17 escuelas diferentes, ubicadas en distintas zonas del área metropolitana de Monterrey, de 1998 a 2008. Resultados. Se obtuvieron niveles séricos de 9.6 ± 3.0 (µg/dL rango de 3.18 a 20.88) en 1998 y de 4.5±4.8 µg/dL (rango de 3.3 a 53.7) en 2008, lo que mostró una disminución de 2.1 veces en nivel de Pb (p<0.01). Conclusiones. La reducción de los niveles séricos de Pb demuestran los mejores controles ambientales e industriales y probablemente el éxito de retirar el Pb de la gasolina durante los años noventa.
Objective. To establish the blood lead concentration and associated risk factors in schoolchildren during 1998 and 2008. Materials and methods. A blood lead screening was conducted in schoolchildren of 6-12 years of age, enrolled in 17 elementary schools of the metropolitan area of Monterrey, México, during 1998 and 2008. Results. The mean blood lead level were 9.6 ± 3.0 (µg/dL range of 3.18 to 20.88) in 1998 and 4.5±4.8 µg/dL (range of 3.3 to 53.7) showing a 2.1-times reduction in blood lead levels (p<0.01). Conclusions. This reduction in blood lead levels demonstrate environmental and industrial control improvements and the benefits of fading out the leaded gasoline during the 1990's.
Subject(s)
Durapatite/chemistry , Fluorides, Topical/chemistry , Fluorides/chemistry , Quaternary Ammonium Compounds/chemistry , Silicic Acid/chemistry , Acidulated Phosphate Fluoride/chemistry , Apatites/chemistry , Crystallography, X-Ray , Sodium Fluoride/chemistry , Solubility , Spectroscopy, Fourier Transform InfraredABSTRACT
Fluoride varnishes play an important role in the prevention of dental caries, promoting the inhibition of demineralization and the increase of remineralization. Objective: This study aimed to analyze the amount of fluoride released into water and artificial saliva from experimental TiF4 and NaF varnishes, with different concentrations, for 12 h. Material and Methods: Fluoride varnishes were applied on acrylic blocks and then immersed in 10 ml of deionized water and artificial saliva in polystyrene bottles. The acrylic blocks were divided in seven groups (n=10): 1.55% TiF4 varnish (0.95% F, pH 1.0); 3.10% TiF4 varnish (1.90% F, pH 1.0); 3.10% and 4% TiF4 varnish (2.45% F, pH 1.0); 2.10% NaF varnish (0.95% F, pH 5.0); 4.20% NaF varnish (1.90% F, pH 5.0); 5.42% NaF varnish (2.45% F, pH 5.0) and control (no treatment, n=5). The fluoride release was analyzed after 1/2, 1, 3, 6, 9 and 12 h of exposure. The analysis was performed using an ion-specific electrode coupled to a potentiometer. Two-way ANOVA and Bonferroni's test were applied for the statistical analysis (p<0.05). Results: TiF4 varnishes released larger amounts of fluoride than NaF varnishes during the first 1/2 h, regardless of their concentration; 4% TiF4 varnish released more fluoride than NaF varnishes for the first 6 h. The peak of fluoride release occurred at 3 h. There was a better dose-response relationship among the varnishes exposed to water than to artificial saliva. Conclusions: The 3.10% and 4% TiF4 -based varnishes have greater ability to release fluoride into water and artificial saliva compared to NaF varnish; however, more studies must be conducted to elucidate the mechanism of action of TiF4 varnish on tooth surface. .
Subject(s)
Cariostatic Agents/chemistry , Fluorides, Topical/chemistry , Fluorides/chemistry , Saliva, Artificial/chemistry , Sodium Fluoride/chemistry , Titanium/chemistry , Dental Caries/prevention & control , Reference Values , Statistics, Nonparametric , Surface Properties , Time Factors , Tooth Remineralization , Water/chemistryABSTRACT
Os dentifrícios de baixa concentração de fluoreto têm sido sugeridos como alternativa para reduzir o risco de fluorose dentária, embora não haja consenso quanto a sua eficácia clínica, a qual pode ser aumentada quando o pH é ácido. Este estudo clínico randomizado teve como objetivo avaliar o efeito anti-cárie do pH e da concentração de fluoreto presente em dentifrícios líquidos, em crianças com diferentes status de atividade cariosa. Crianças de 2-4 anos de idade residentes em uma área fluoretada (0,6-0,8 ppm F), com (A) e sem (I) lesões de cárie ativa foram distribuídas aleatoriamente em três grupos de acordo com o tipo de dentifrício utilizado: Grupo 1 (n=48-A/56-I): 550 ppm F pH 4,5, Grupo 2 (n=56-A/48-I) 1100 ppm F pH 7,0, Grupo 3 (n=52-A/55-I): 550 ppm F pH 7,0. O número de lesões tornando-se ativas/cavidades ou inativas, respectivamente, foi avaliado clinicamente após 12 meses, podendo-se determinar se as lesões progrediram ou regrediram. Além disso, as lesões de mancha branca foram avaliadas através da técnica de quantificação de fluorescência induzida por luz (Quantitative Light-Induced Fluorescence - QLF) em uma subamostra de 75 crianças. A concentração de fluoreto nas unhas dos pés e no biofilme dentário também foi avaliada após 6 meses de uso dos dentifrícios. A progressão de cárie seguiu um padrão decrescente de acordo com o dentifrício utilizado (G3>G2>G1), independentemente da atividade de cárie da criança, mas diferenças significativas foram detectadas apenas para a progressão e o incremento de cárie (G1 < G3) no grupo de crianças cárie-ativas, quando avaliadas por inspeção visual. Para a regressão de cárie, os valores encontrados para os 3 grupos foram mais parecidos entre si, não havendo diferenças significativas entre osgrupos. Por outro lado, a análise com o QLF não detectou diferença significativa entre os Grupos 1 e 2, mas eles tiveram um desempenho significativamente melhor que o Grupo 3. Concentrações de fluoreto...
Low-F dentifrices have been suggested as an alternative to reduce the risk of dental fluorosis, although there is no consensus on their clinical efficacy, which may be increased when the pH is acidic.The present randomized clinical trial evaluated the anticaries effect of low-F acidic liquid dentifrice in children at different caries activity status. Two-to-four-year-old schoolchildren living in a fluoridated area (0.6 0.8 ppm F), with (A) or without (I) active caries lesions were randomly allocated into 3 groups differing according to the type of dentifrice used over 12 months: Group 1 (n=48-A/56-I): 550 ppm F pH 4.5, Group 2 (n=56-A/48-I) 1100 ppm F pH 7.0, Group 3 (n=52-A/55-I): 550 ppm F pH 7.0. The number of lesions becoming active/cavities or inactive was clinically evaluated determining progression or regression. Additionally, the white spot lesions were evaluated by the quantitative light-induced fluorescence (QLF) method in a subsample of 75 children. Toenail and plaque fluoride concentration were also evaluated 6 months after the use of the dentifrices. Plaque samples were collected 5 and 60 minutes after the last use of the dentifrices. Caries net increment followed a decreasing pattern according to the dentifrice used (G3>G2>G1) regardless caries activity, but significant differences were detected only for caries progression and net increment (G1 < G3) for the cariesactive group when evaluated through visual inspection. For the regression, the values found for the three groups were more similar, without significant differences. QLF analysis detected no significant difference between Groups 1 and 2, but they performed significantly better than Group 3. Toenail fluoride concentration significantly lower was observed when children used the low-fluoride dentifrices. Plaque F concentration was significantly higher for Group 2 compared to group 3, egardless the time, while Group 1 did not significantly differ Group 2, but was...
Subject(s)
Humans , Animals , Male , Child, Preschool , Dental Caries/prevention & control , Dental Caries/drug therapy , Dentifrices/chemistry , Fluorides, Topical/chemistry , Analysis of Variance , Dentifrices/therapeutic use , Fluoridation , Fluorine/analysis , Fluorides, Topical/therapeutic use , Dental Plaque/drug therapy , Treatment OutcomeABSTRACT
Os dentifrícios de baixa concentração de fluoreto têm sido sugeridos como alternativa para reduzir o risco de fluorose dentária, embora não haja consenso quanto a sua eficácia clínica, a qual pode ser aumentada quando o pH é ácido. Este estudo clínico randomizado teve como objetivo avaliar o efeito anti-cárie do pH e da concentração de fluoreto presente em dentifrícios líquidos, em crianças com diferentes status de atividade cariosa. Crianças de 2-4 anos de idade residentes em uma área fluoretada (0,6-0,8 ppm F), com (A) e sem (I) lesões de cárie ativa foram distribuídas aleatoriamente em três grupos de acordo com o tipo de dentifrício utilizado: Grupo 1 (n=48-A/56-I): 550 ppm F pH 4,5, Grupo 2 (n=56-A/48-I) 1100 ppm F pH 7,0, Grupo 3 (n=52-A/55-I): 550 ppm F pH 7,0. O número de lesões tornando-se ativas/cavidades ou inativas, respectivamente, foi avaliado clinicamente após 12 meses, podendo-se determinar se as lesões progrediram ou regrediram. Além disso, as lesões de mancha branca foram avaliadas através da técnica de quantificação de fluorescência induzida por luz (Quantitative Light-Induced Fluorescence - QLF) em uma subamostra de 75 crianças. A concentração de fluoreto nas unhas dos pés e no biofilme dentário também foi avaliada após 6 meses de uso dos dentifrícios. A progressão de cárie seguiu um padrão decrescente de acordo com o dentifrício utilizado (G3>G2>G1), independentemente da atividade de cárie da criança, mas diferenças significativas foram detectadas apenas para a progressão e o incremento de cárie (G1 < G3) no grupo de crianças cárie-ativas, quando avaliadas por inspeção visual. Para a regressão de cárie, os valores encontrados para os 3 grupos foram mais parecidos entre si, não havendo diferenças significativas entre osgrupos. Por outro lado, a análise com o QLF não detectou diferença significativa entre os Grupos 1 e 2, mas eles tiveram um desempenho significativamente melhor que o Grupo 3. Concentrações de fluoreto...
Low-F dentifrices have been suggested as an alternative to reduce the risk of dental fluorosis, although there is no consensus on their clinical efficacy, which may be increased when the pH is acidic.The present randomized clinical trial evaluated the anticaries effect of low-F acidic liquid dentifrice in children at different caries activity status. Two-to-four-year-old schoolchildren living in a fluoridated area (0.6 0.8 ppm F), with (A) or without (I) active caries lesions were randomly allocated into 3 groups differing according to the type of dentifrice used over 12 months: Group 1 (n=48-A/56-I): 550 ppm F pH 4.5, Group 2 (n=56-A/48-I) 1100 ppm F pH 7.0, Group 3 (n=52-A/55-I): 550 ppm F pH 7.0. The number of lesions becoming active/cavities or inactive was clinically evaluated determining progression or regression. Additionally, the white spot lesions were evaluated by the quantitative light-induced fluorescence (QLF) method in a subsample of 75 children. Toenail and plaque fluoride concentration were also evaluated 6 months after the use of the dentifrices. Plaque samples were collected 5 and 60 minutes after the last use of the dentifrices. Caries net increment followed a decreasing pattern according to the dentifrice used (G3>G2>G1) regardless caries activity, but significant differences were detected only for caries progression and net increment (G1 < G3) for the cariesactive group when evaluated through visual inspection. For the regression, the values found for the three groups were more similar, without significant differences. QLF analysis detected no significant difference between Groups 1 and 2, but they performed significantly better than Group 3. Toenail fluoride concentration significantly lower was observed when children used the low-fluoride dentifrices. Plaque F concentration was significantly higher for Group 2 compared to group 3, egardless the time, while Group 1 did not significantly differ Group 2, but was...
Subject(s)
Humans , Animals , Male , Child, Preschool , Dental Caries/prevention & control , Dental Caries/drug therapy , Dentifrices/chemistry , Fluorides, Topical/chemistry , Analysis of Variance , Dentifrices/therapeutic use , Fluoridation , Fluorine/analysis , Fluorides, Topical/therapeutic use , Dental Plaque/drug therapy , Treatment OutcomeABSTRACT
The aim of this in vitro study was to evaluate the shear bond strength of brackets after pre-treatment with different fluoride solutions. This study used 48 freshly extracted sound bovine incisors that were randomly assigned to 4 experimental groups (n=12). CG: (control) without treatment; NF: 4 min application of neutral fluoride; APF: application of 1.23% acidulated phosphate fluoride (APF) for 4 min; and SFV: application of 5% sodium fluoride varnish for 6 h. For each group, after surface treatment, prophylaxis of enamel and bracket bonding with Transbond XT composite resin (3M) were performed following the manufacturer's specifications. The shear bond strength was performed with a universal testing machine 24 h after fixing the brackets. The tooth surfaces were analyzed to verify the adhesive remnant index (ARI). Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). There was statistically significant difference among the groups (p<0.0001). CG and NF groups presented significantly higher bond strength than APF and SFV. There was no significant difference between CG and NF or between APF and SFV (p>0.05). The analysis of ARI scores revealed that most failures occurred at the enamel-resin interface. It may be concluded that the pre-treatment of enamel with 1.23% APF and 5% SFV prior to fixing orthodontic brackets reduces shear bond strength values.
O objetivo deste estudo foi o de avaliar in vitro a resistência adesiva de bráquetes após o pré-tratamento do esmalte com diferentes soluções fluoretadas. Foram utilizados 48 incisivos bovinos hígidos recém-extraídos que foram aleatoriamente divididos em 4 grupos experimentais (n=12). CG (controle): sem tratamento; FN: aplicação de flúor neutro por 4 min; FFA: aplicação de flúor fosfato acidulado (FFA) a 1,23% por 4 min; e VFS: aplicação de verniz de fluoreto de sódio a 5% por 6 h. Após o tratamento dos grupos, foi realizada a profilaxia do esmalte e os bráquetes foram fixados utilizando o compósito Transbond XT (3M), seguindo as especificações do fabricante. A resistência adesiva foi verificada através do teste de cisalhamento, realizado na Máquina de Ensaio Universal DL-2000 24 h após a fixação dos bráquetes. As superfícies dos dentes foram analisadas para verificação do índice de adesivo remanescente (IAR). Por meio dos testes estatísticos ANOVA e Tukey (α=5%), observou-se diferença estatisticamente significante entre os grupos estudados (p<0,0001), sendo que GC e FN, apresentaram valores superiores de resistência adesiva quando comparados aos grupos FFA e VFS, porém GC-NF e FFA-VFS não apresentaram diferenças estatisticas entre si (p>0,05). A análise dos escores do IAR revelou que grande parte das falhas ocorreram na interface esmalte-resina. Conclui-se que o tratamento do esmalte com FFA 1,23% e VFS a 5%, previamente à fixação de bráquetes ortodônticos, reduziu os valores de resistência adesiva ao cisalhamento.
Subject(s)
Animals , Cattle , Cariostatic Agents/chemistry , Dental Bonding , Fluorides/chemistry , Orthodontic Brackets , Adhesiveness , Acid Etching, Dental/methods , Acidulated Phosphate Fluoride/chemistry , Dental Alloys/chemistry , Dental Enamel/ultrastructure , Dental Stress Analysis/instrumentation , Fluorides, Topical/chemistry , Materials Testing , Phosphoric Acids/chemistry , Random Allocation , Resin Cements/chemistry , Shear Strength , Stress, Mechanical , Surface Properties , Saliva, Artificial/chemistry , Sodium Fluoride/chemistry , Stainless Steel/chemistry , Temperature , Time Factors , Water/chemistryABSTRACT
Background and Objectives: One of the most difficult problems encountered in orthodontic treatment with fixed appliance is the control of enamel demineralization around the brackets. Fluoride-releasing bonding adhesives were introduced to aid in the prevention of demineralization adjacent to orthodontic brackets. Hence, an in vitro study was conducted to evaluate and compare demineralization adjacent to the orthodontic bracket and the bond strength using fluoride-releasing adhesive and conventional adhesive. Materials and Methods: One hundred and twenty healthy extracted premolars were selected for the study and were divided into two groups, each group consisting of 60 teeth. Both groups were further divided into three subgroups consisting of 20 samples each. Samples of subgroups A and B were bonded with two prototypes of fluoride-releasing adhesives (i.e. Rely-a-bond and Tru-bond). Samples of subgroup C (ortho-one) were bonded with conventional non-fluoride-releasing adhesive. Group I samples were subjected to demineralization in an acidic medium (methyl cellulose buffered with acetic acid at a pH of 4.5) for 4 weeks, which were later observed under a stereomicroscope. Group II samples were tested for shear bond strength using the Instron Universal testing machine. Results: Both fluoride-releasing adhesives showed statistically significant lower enamel demineralization around the bracket when compared with the conventional adhesive. There was no statistically significant difference on comparing the demineralization between the two prototypes of fluoride-releasing adhesive. Evaluation of shear bond strength revealed that there was no significant difference between the subgroups. Conclusion: Fluoride-releasing adhesives might aid in the prevention of demineralization adjacent to the orthodontic bracket with acceptable bond strength.
Subject(s)
Bisphenol A-Glycidyl Methacrylate/chemistry , Bisphenol A-Glycidyl Methacrylate/therapeutic use , Cariostatic Agents/administration & dosage , Cariostatic Agents/chemistry , Delayed-Action Preparations , Dental Bonding , Dental Enamel/pathology , Fluorides, Topical/administration & dosage , Fluorides, Topical/chemistry , Humans , Orthodontic Brackets/adverse effects , Polyethylene Glycols/chemistry , Polyethylene Glycols/therapeutic use , Resin Cements/chemistry , Resin Cements/therapeutic use , Shear Strength , Tooth Demineralization/etiology , Tooth Demineralization/pathology , Tooth Demineralization/prevention & controlABSTRACT
The aim of the present study was to evaluate the in vitro caries preventive effect of fluoridated orthodontic resins under pH cycling with two types of acid demineralizing saliva. Brackets were bonded to 60 bovine incisors, using either Transbond Plus Color Change (n=30) or Orthodontic Fill Magic (n=30) orthodontic resins. Each group of resin was divided into 3 subgroups (n=10): immersion in remineralizing artificial saliva for 14 days, pH cycling with high cariogenic challenge in acid saliva with pH 5.5, and acid saliva with pH 4.5. After 14 days of pH cycling, the caries preventive effect on the development of white spot lesion was evaluated considering the presence of inhibition zones to white spot lesions using two scores: 0= absence and 1= presence. Kruskal Wallis and Mann-Whitney tests (a=0.05) were used. Formation of white spot lesions was observed only under pH cycling using acid saliva with pH 4.5; with Transbond Plus Color Change being significantly more effective (p<0.05) in preventing the appearance of white spot lesions effect than Orthodontic Fill Magic. The acidity of the demineralizing solution influenced the formation of white spot lesions around orthodontic brackets under highly cariogenic conditions. Transbond Plus Color Change resin presented higher caries preventive effect than Orthodontic Fill Magic.
O objetivo do presente estudo foi avaliar in vitro o efeito preventivo a cárie de resinas ortodônticas fluoretadas submetidas à ciclagem de pH utilizando dois tipos de saliva desmineralizadora. Bráquetes de incisivos centrais foram colados em 60 incisivos bovinos, utilizando a resina ortodôntica Transbond Plus Color Change (n=30) ou Fill Magic (n=30). Cada grupo foi dividido em 3 subgrupos (n=10): imersão em saliva artificial remineralizante por 14 dias e simulação de alto desafio cariogênico com ciclagem de pH em saliva ácida com pH 5,5 ou pH 4,5. Após 14 dias de ciclagem de pH, o efeito preventivo de cárie foi avaliado por meio da formação de halo de inibição da mancha branca, adotando-se os escores: 0-ausência e 1-presença. Os testes Kruskal Wallis e Man-Whitney (a=0,05) foram aplicados. A formação de lesões de mancha branca foi observada somente na ciclagem de pH com saliva ácida a pH 4,5; sendo o Transbond Plus Color Change significantemente mais efetivo na prevenção ao desenvolvimento de mancha branca quando comparados ao Fill Magic (p<0,05). O pH da solução desmineralizante influenciou na formação de lesões de mancha branca circunjacentes aos bráquetes em condições de alto desafio cariogênico. A Transbond Plus Color Change apresentou maior efeito preventivo de cárie em relação ao Fill Magic.
Subject(s)
Animals , Cattle , Acrylic Resins/chemistry , Cariostatic Agents/administration & dosage , Dental Caries/prevention & control , Dental Enamel/drug effects , Fluorides, Topical/administration & dosage , Tooth Demineralization/prevention & control , Bisphenol A-Glycidyl Methacrylate/chemistry , Cariostatic Agents/chemistry , Composite Resins/chemistry , Diet, Cariogenic , Dental Bonding/methods , Dental Cements/chemistry , Fluorides, Topical/chemistry , Orthodontic Brackets , Resin Cements/chemistry , Statistics, Nonparametric , Saliva, Artificial/adverse effectsABSTRACT
OBJECTIVE: The objective of this study was to evaluate the effect of desensitizing agents containing different amounts of fluoride on the shear bond strength of a dual polymerized resin cement and a resin-modified glass ionomer cement (RMGIC) to dentin. MATERIAL AND METHODS: One hundred human molars were mounted in acrylic resin blocks and prepared until the dentin surface was exposed. The specimens were treated with one of four desensitizing agents: Bifluorid 12, Fluoridin, Thermoline and PrepEze. The remaining 20 specimens served as untreated controls. All groups were further divided into 2 subgroups in which a dual polymerized resin cement (Bifix QM) or a resin-modified glass ionomer cement (AVANTO) was used. The shear bond strength (MPa) was measured using a universal testing machine at a 0.5 mm/min crosshead speed. The data were analyzed statistically with a 2-way ANOVA, Tukey HSD test and regression analysis (α=0.05). The effect of the desensitizing agents on the dentin surface was examined by scanning electron microscopy. RESULTS: The fluoride-containing desensitizing agents affected the bond strength of the resin-based cements to dentin (p<0.001). PrepEze showed the highest bond strength values in all groups (p<0.001). CONCLUSION: Regression analysis showed a reverse relation between bond strength values of resin cements to dentin and the amount of fluoride in the desensitizing agent (p<0.05).
Subject(s)
Humans , Cariostatic Agents/chemistry , Dental Bonding , Dentin Desensitizing Agents/chemistry , Dentin-Bonding Agents/chemistry , Dentin/ultrastructure , Fluorides/chemistry , Resin Cements/chemistry , Adhesiveness , Calcium Fluoride/chemistry , Composite Resins/chemistry , Dental Stress Analysis/instrumentation , Fluorides, Topical/chemistry , Glass Ionomer Cements/chemistry , Materials Testing , Microscopy, Electron, Scanning , Shear Strength , Stress, Mechanical , Sodium Fluoride/chemistry , Temperature , Time Factors , Water/chemistryABSTRACT
The objective of this study was to assess the salivary residual effect of fluoride dentifrice on human enamel subjected to an erosive challenge. This crossover in situ study was performed in two phases (A and B), involving ten volunteers. In each phase, they wore acrylic palatal appliances, each containing 3 human enamel blocks, during 7 days. The blocks were subjected to erosion by immersion of the appliances in a cola drink for 5 minutes, 4 times a day. Dentifrice was used to brush the volunteers teeth, 4 times a day, during 1 minute, before the appliance was replaced into the mouth. In phases A and B the dentifrices used had the same formulation, except for the absence (PD) or presence (FD) of fluoride, respectively. Enamel alterations were determined using profilometry, microhardness ( percentSMHC), acid- and alkali-soluble F analysis. The data were tested using ANOVA (p < 0.05). The concentrations (mean ± SD) of alkali- and acid-soluble F (µgF/cm²) were, respectively, PD: 1.27ª ± 0.70/2.24A ± 0.36 and FD: 1.49ª ± 0.44/2.24A ± 0.67 (p > 0.05). The mean wear values (± SD, µm) were PD: 3.63ª ± 1.54 and FD: 3.54ª ± 0.90 (p > 0.05). The mean percentSMHC values (± SD) were PD: 89.63ª ± 4.73 and FD: 87.28ª ± 4.01 (p > 0.05). Thus, we concluded that the residual fluoride from the fluoride-containing dentifrice did not protect enamel against erosion.
Subject(s)
Adult , Humans , Young Adult , Cariostatic Agents/therapeutic use , Dental Enamel/drug effects , Dentifrices/chemistry , Fluorides, Topical/therapeutic use , Saliva/chemistry , Tooth Erosion/prevention & control , Analysis of Variance , Cross-Over Studies , Carbonated Beverages/adverse effects , Cariostatic Agents/chemistry , Double-Blind Method , Fluorides, Topical/chemistry , Saliva/physiology , Tooth Abrasion/prevention & control , Tooth Erosion/chemically induced , Young AdultABSTRACT
O presente trabalho teve como objetivo avaliar, in situ, o efeito remineralizador de um selante resinoso e um cimento de ionômero de vidro aplicados em esmalte dental bovino desmineralizado, associados a um verniz fluoretado. Para tal, 120 blocos de esmalte bovinos (4x4x2,5mm), previamente polidos e desmineralizados, foram montados (dois a dois) simulando uma fissura artificial em "V" (1200) e seladas com os respectivos materiais: 1- selante resinoso (Delton Dentsply); 2 cimento de ionômero de vidro convencional (Ketac-Molar Easy Mix 3M ESPE) e 3 - controle (sem material selador). O período experimental foi realizado em 2 fases de 14 dias (Sem e Com verniz fluoretado Duraphat - A. Nattermann & Cie) nas quais 10 voluntários utilizaram o dispositivo palatino, contendo 1 espécime de cada grupo. Decorridos os períodos experimentais, os espécimes foram seccionados no centro do material selador, sendo uma metade utilizada para análise do conteúdo de flúor fracamente ligado ao esmalte (CaF2), enquanto a outra metade analisou a porcentagem de volume mineral, por meio de teste de microdureza longitudinal, aplicados em 3 diferentes distâncias do material selador (Externo, Médio e Interno), em 8 profundidades distintas (10, 30, 50, 70, 90, 110, 220 e 330 µm). Os dados foram analisados estatisticamente (Análise de Variância e o Teste de Tukey, p<0,05) constatando na análise do flúor fracamente ligado ao esmalte que o cimento de ionômero de vidro, apresentou os maiores valores de flúor no esmalte, com ou sem utilização do verniz fluoretado, já o material 1 (Delton) não diferiu do 3 (controle), independente da utilização ou não do verniz fluoretado. Observou-se que no esmalte não recoberto pelo selante (Externo) a porcentagem de volume mineral, obteve efeito significativo da aplicação do verniz (p=0,05). As profundidades de 10 e 30 µm apresentaram diferenças estatísticas (p<0,0001) em relação às demais, na porcentagem de volume mineral, em todas as distâncias avaliadas (Externo, Médio e Interno). Não foi observado efeito significativo do material selador utilizado, com e sem verniz fluoretado. Além disso, não foi observada interação significativa entre os fatores analisados. Conclui-se, portanto, que embora a aplicação do verniz fluoretado seja capaz de aumentar os níveis de flúor na camada superficial do esmalte desmineralizado, não se observa o mesmo aumento ou recuperação proporcional na dureza desse esmalte.(AU)
The remineralization effect of a resin sealant and a glass-ionomer cement, associated with the use of a fluoride varnish, on demineralized bovine enamel was evaluated in this in situ study. One hundred and twenty bovine enamel blocks (4X4X2.5mm), previously polished and demineralized, were mounted (2 by 2) to simulate an artificial fissure in a "V" shape (120o) and sealed with: 1- resin sealant (Delton Dentsply); 2 conventional glassionomer cement (Ketac-Molar Easy Mix 3M ESPE) and 3 - control (no sealing material). The study was conducted in 2 phases of 14 days (With and Without fluoride varnish Duraphat - A. Nattermann & Cie), during which 10 volunteers used a palatal appliance containing 1 specimen of each group. After the experimental periods, the specimens were sectioned through the center of the sealing material; one half was used for determination of looselybound fluoride (CaF2) formed on the enamel, while the other was analyzed for percentage of mineral volume, by means of longitudinal microhardness. The microhardness was determined at 3 different distances from the sealing material (External, Medium and Internal), and at 8 different depths (10, 30, 50, 70, 90, 110, 220 and 330 µm). Data were analyzed by Analysis of Variance and Tukey test, with p at 0.05. With respect to loosely-bound fluoride, the glass-ionomer cement presented the higher values, with or without the use of the fluoride varnish. Material 1 (Delton) did not differ from the 3 (control), irrespective of the use or not of fluoride varnish. In the area of enamel free of sealant (External), the percentage of mineral volume was higher with the use of the fluoride varnish (p=0.05). The depths of 10 and 30 µm were significantly different (p<0.0001) from all others, in all areas evaluated (External, Medium and Internal). No significant effect of sealing material was observed, with or without fluoride varnish. Additionally, no significant interaction was observed among the factors analyzed.(AU)