The in vivo efficacy of Fluorinex topical fluoridation treatment.

OBJECTIVE: This randomized, single-controlled study was performed to validate in vivo the efficacy of single Fluorinex treatment by examining fluoride incorporation into enamel using electron microscopy. METHOD AND MATERIALS: Twenty healthy participants referred for routine dental treatment which also required extractions of at least two teeth as part of their treatment plan were included in this study. For each participant, one randomly selected tooth was extracted and sent for blind electron microscopic fluoride assay (control, C). Next, following a single Fluorinex treatment, the second (test, T) tooth was extracted and sent for the same assay. Intra-individual and intergroup fluoride content comparisons were performed, between control and test teeth. RESULTS: Highly significant intra-individual and intergroup differences were found between the treated and untreated teeth. Fluoride atomic percent (at%) and weight percent (wt%) estimated least squares means of untreated group were found to be 0.56 and 0.48, and in the treated group 17.35 and 14.35. This increase in fluoride at% [16.78 ± 2.3 (SE)], was also significant statistically (P < .0001); likewise, the increase in fluoride wt % [13.86 ± 1.97 (SE)] was similarly significant (P < .0001). The system was well tolerated by the participants with minimal transitional mild side effects. CONCLUSION: In vivo fluoride application using the active Fluorinex system resulted in a significant increase of fluoride content in the enamel of adult permanent teeth compared to untreated internal controls.

Salivary retention after application of fluoride gel using toothbrush or tray: a crossover trial

Currently, there are no studies in the literature evaluating salivary fluoride retention after small amounts of fluoride gel are applied to children's teeth. Therefore, the objective of the present study was to compare salivary retention after gel application using a toothbrush or by traditional application with trays. In this crossover study, children with active caries (n = 10) were randomized into one of the following treatment groups: a) application of fluoride gel using a tray (control), or b) application of fluoride gel with a toothbrush (treatment). After a 7-day washout period, the treatments were inverted. Unstimulated saliva samples were collected at baseline and 0.5, 5, 15, 30, 60 and 120 minutes after acidulated phosphate fluoride (APF) gel application in order to analyze fluoride retention in saliva. The area under the curve (AUC) was also calculated. There were no differences in fluoride retention after application of small amounts of APF with a toothbrush compared to traditional gel application using trays at all time points studied, and no differences in AUC were observed (Student t-test, p > 0.05). These results suggest that application of fluoride gel in children using a toothbrush can be utilized as an option rather than traditional trays, since the same salivary retention of fluoride is obtained using a lower dose.

Salivary retention after application of fluoride gel using toothbrush or tray: a crossover trial.

Currently, there are no studies in the literature evaluating salivary fluoride retention after small amounts of fluoride gel are applied to children's teeth. Therefore, the objective of the present study was to compare salivary retention after gel application using a toothbrush or by traditional application with trays. In this crossover study, children with active caries (n = 10) were randomized into one of the following treatment groups: a) application of fluoride gel using a tray (control), or b) application of fluoride gel with a toothbrush (treatment). After a 7-day washout period, the treatments were inverted. Unstimulated saliva samples were collected at baseline and 0.5, 5, 15, 30, 60 and 120 minutes after acidulated phosphate fluoride (APF) gel application in order to analyze fluoride retention in saliva. The area under the curve (AUC) was also calculated. There were no differences in fluoride retention after application of small amounts of APF with a toothbrush compared to traditional gel application using trays at all time points studied, and no differences in AUC were observed (Student t-test, p > 0.05). These results suggest that application of fluoride gel in children using a toothbrush can be utilized as an option rather than traditional trays, since the same salivary retention of fluoride is obtained using a lower dose.

Effect of Er,Cr:YSGG laser and professional fluoride application on enamel demineralization and on fluoride retention.

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.

Dielectrophoresis: a model to transport drugs directly into teeth.

The article describes an innovative delivery system based on the principles of dielectrophoresis to transport drugs directly into site-specific intraoral targets. The hypothesis that a drug can be driven into tooth enamel during the application of an applied electrical potential difference was tested by the authors in in vitro studies comparing dielectrophoresis to diffusion to transport carbamide peroxide and fluoride. The studies showed that these agents can be transported directly into teeth using an alternating current (AC) electric field more effectively than diffusion. It was found that a 20-min bleaching treatment on human teeth with dielectrophoresis increased carbamide peroxide absorption by 104% and, on average, improved the change in shade guide unit 14 times from 0.6 SGU to 9 SGU. After applying a 1.23% acidulated phosphate fluoride gel to bovine incisors for 20 min by dielectrophoresis or diffusion, analysis with wavelength dispersive spectrometry determined that dielectrophoresis doubled fluoride uptake in the superficial layers compared to diffusion, and drove the fluoride significantly deeper into enamel with an uptake 600% higher than diffusion at 50 µm depth. Finally, dielectrophoresis promises to be a viable model that can potentially be used clinically to deliver other targeted drugs of variable molecular weight and structure.

The roughness, microhardness, and surface analysis of nanocomposites after application of topical fluoride gels.

OBJECTIVES: Application of acidulated phosphate fluoride (APF) gels has long been considered to cause deterioration of composite surfaces. The aims of this study were to demonstrate that nanocomposite surfaces were not affected by some APF gels and to investigate the possible underlying mechanisms. METHODS: The elemental composition and viscosity of 3 acidulated phosphate fluoride (APF) agents (60 Second Taste Gel, Topex, and Zap) and 1 neutral fluoride agent (pH7 Gel) were analyzed. Subsequently, 320 specimens of 3 nanocomposites (Premisa, Filtek Z350, and Grandio) and a microhybrid composite (Estelite Sigma) with 80 specimens for each composite were randomly divided into 5 groups (n=16) and treated with 4 fluoride gels as well as distilled water which served as the control. Fluoride gels were applied on composite resin surfaces 4 times, 30 min each time. The roughness and microhardness were measured after treatments. Qualitative examination of the surface degradation of the composites was carried out with Fourier transforming infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). RESULTS: Topex and Zap did not cause surface changes of composite resins, the possible reason being ascribed to the presence of magnesium aluminum silicate (MAS) clays. In contrast, 60 Second Taste Gel treatments caused significant roughness increase, microhardness decrease, more prominent filler dissolution, and IR spectral changes of Premisa, Filtek Z350, and Grandio. Estelite Sigma was less affected by the 4 fluoride gels. SIGNIFICANCE: The composite surfaces were not affected by Topex or Zap even after extended treatments. These two APF gels may be more suitable for clinical applications.

Fluoride release by restorative materials before and after a topical application of fluoride gel.

The release of fluoride from restorative materials (Vitremer, Ketac-Fil, Fuji II LC and Freedom) was evaluated during two 15-day periods, before and after a topical application of acidulated phosphate fluoride gel (APF). For each material, 6 specimens were made, which were immersed in 2 ml of deionized water. The fluoride concentration dosages in the solutions were read at intervals of 24 hours for 15 days. After this period, the specimens of each material received treatment with APF gel for 4 minutes and the fluoride released was analyzed at 24-hour intervals during the following 15 days. The analysis of variance and the Tukey test (p < 0.05) showed that the total mean fluoride released during the initial 15 days was greater for Vitremer and Ketac-Fil and lower for Fuji II LC and Freedom; and in the final 15 days there was a difference in release readings, with the greatest value for Vitremer, followed by Fuji II LC, Ketac-Fil and Freedom. The comparison of the results between the 1st day and the 16th day (after gel application) showed a greater fluoride release on the 16th day for Vitremer, Fuji II LC and Freedom and was equal for Ketac-Fil. Although all the materials evaluated gained fluoride with the application of APF, the data suggest that the resin-modified ionomers are more efficient in releasing fluoride to the medium than the other materials.

The effect of home-use fluoride gels on glass-ionomer, compomer and composite resin restorations.

The purpose of this study was to investigate the resistance to dissolution by two home-use fluoride gels on the surface integrity of glass-ionomer, resin modified glass-ionomer, compomer and composite resin restorations. Class V cavities prepared in extracted teeth were restored with a glass-ionomer (Fuji II), a resin modified glass-ionomer (Vitremenr), two compomers (Dyract and F-2000) and a composite resin (Z-100). Groups of five specimens of each material were treated for 24 h with one of the following: (i). distilled water, (ii). neutral fluoride gel and (iii). acidulated phosphate fluoride (APF) gel. Surface degradation of the restorations was studied using standard electron microscopy (SEM), rated according to specific criteria and statistically analysed by the Wilcoxon test (rank sums). Acidulated phosphate fluoride was found to have a significant effect on all examined materials, while minimal effects resulted from the neutral fluoride gel compared with the control group. The effect of home-use fluoride gels on glass-ionomer, compomer and composite resin restorations.

Fluoride release by restorative materials before and after a topical application of fluoride gel

The release of fluoride from restorative materials (Vitremer, Ketac-Fil, Fuji II LC and Freedom) was evaluated during two 15-day periods, before and after a topical application of acidulated phosphate fluoride gel (APF). For each material, 6 specimens were made, which were immersed in 2 ml of deionized water. The fluoride concentration dosages in the solutions were read at intervals of 24 hours for 15 days. After this period, the specimens of each material received treatment with APF gel for 4 minutes and the fluoride released was analyzed at 24-hour intervals during the following 15 days. The analysis of variance and the Tukey test (p < 0.05) showed that the total mean fluoride released during the initial 15 days was greater for Vitremer and Ketac-Fil and lower for Fuji II LC and Freedom; and in the final 15 days there was a difference in release readings, with the greatest value for Vitremer, followed by Fuji II LC, Ketac-Fil and Freedom. The comparison of the results between the 1st day and the 16th day (after gel application) showed a greater fluoride release on the 16th day for Vitremer, Fuji II LC and Freedom and was equal for Ketac-Fil. Although all the materials evaluated gained fluoride with the application of APF, the data suggest that the resin-modified ionomers are more efficient in releasing fluoride to the medium than the other materials

Efeito do gel de fluorfato (neutro e acidulado) em lesöes incipientes de cárie em esmalte: remineralizaçäo ou erosäo? Um estudo in vitro / Effect of fluoridated gel (neutral and acidulated) on early enamel caries: remineralization or erosion? An in vitro study

A proposiçäo deste estudo foi avaliar, in vitro, as alteraçöes microscópicas (em luz polarizada), ocorridas em lesöes artificiais de cárie, produzidas em esmalte bovino e submetidas à açäo de géis fluoretados acidulado e neutro. Para tanto, 18 incisivos bovinos foram divididos aleatoriamente em cinco grupos: 1. exposto à açäo de fluorfosfato acidulado (FFA) por um minuto (Nupro, Dentsplay); 2. FFA por quatro minutos (Nupro, Dentsplay); 3. fluorfosfato neutro (FFN) por um minuto (Nupro, Denstsplay); 4. FFN por quatro minutos (Nupro, Dentsplay); 5. controle. Foram produzidas lesöes de cárie, com área padronizada (12,6mm²), em secçöes de esmalte removidas da regiäo central da face vestibular desses elementos dentários. Constatou-se, por meio da análise microscópica, que as lesöes de cárie exposta à açäo do gel fluoretado apresentavam alteraçöes superficiais indicativas de erosäo da camada externa do esmalte, as quais foram bem mais expressivas diante de FFA

Efeito do tempo de aplicaçäo na incorporaçäo, retençäo e açäo anticariogênica do flúor fosfato acidulado: estudo in situ / Study in situ of the effects of different topical treatment times in relation to the anticaries effect of acidulated phosphate fluoride

O efeito do tempo de aplicaçäo tópica na formaçäo (logo após aplicaçäo) e retençäo de flúor (após 28 dias), assim como a açäo anticariogênica do flúor gel fosfato acidulado (FFA) foi estudado através de um modelo in situ. O estudo foi do tipo cruzado de 3 etapas de 28 dias (Controle, FFA-1 min. e 4 min), nas quais 15 voluntários utilizaram dispositivos intra-bucais palatinos contendo 4 blocos de esmalte dental (1 mm abaixo da superfície do acrílico), cobertos com uma tela plástica para acúmulo de placa. Para determinar o flúor formado, 2 blocos adicionais foram aderidos ao acrílico e retirados após aplicaçäo. Os dispositivos intra-bucais foram imersos 3x/dia em sacarose 10 por cento e os voluntários utilizaram dentifrício näo fluoretado, porém bebiam água fluoretada. As determinaçöes de flúor foram realizadas com eletrodo específico após prévia remoçäo de 5 camadas sucessivas de esmalte com HCI 0,5M e a quantidade de esmalte retirada foi estimada pela dosagem colorimétrica de fósforo...

Oral fluoride retention with thixotropic and APF gels and foam-lined and unlined trays.

Ten child volunteers each received four topical fluoride applications using different techniques. The amounts of fluoride applied, recovered from the mouth, and retained in the mouth were calculated for each treatment. The value of patient expectoration following topical F treatment was also evaluated. The tray system with an absorptive liner significantly reduced the amount of gross oral-retained fluoride (p less than 0.01). Expectoration following topical treatment with either an APF or thixotropic gel was a significant adjunct in reducing the net oral-retained F dose (p less than 0.01). When expectoration is done following a topical F treatment, a thixotropic gel may be an added advantage in reducing oral F retention and ingestion. We recommend that suction devices be used during a topical F treatment, but most importantly that the patient be requested to expectorate thoroughly following topical treatment.

Enamel biopsy results of children receiving fluoride tablets.

This study measured the fluoride in tooth enamel of 338 schoolchildren after daily use of acidulated phosphate-fluoride (APF) tablets, and investigated the relationship between observed amounts of enamel fluoride and incidence of caries. Randomly selected study groups received under supervision either one placebo tablet, one APF tablet containing 1 mg fluoride, or 2 APF tablets (3 hours apart) each school day. An abrasive enamel-type biopsy of a maxillary central incisor was taken 30 months after the start of fluoride tablet treatments at the time of the follow-up examinations. Mean fluoride levels in the biopsied enamel from each of the three groups were similar despite a significant restriction in caries in the group receiving two APF tablets per day. These findings suggest that fluoride can restrict dental caries by some mechanism other than fluoride uptake in the enamel.