Slow-release fluoride devices: a literature review

Although the prevalence of caries has decreased dramatically over the past decades, it has become a polarised disease, with most of subjects presenting low caries levels and few individuals accounting for most of the caries affected surfaces. Thus it become evident for the need of clinical approaches directed at these high-risk patients, in order to overcome problems related to compliance and low attendance at dental care centres. Slow-release fluoride devices were developed based on the inverse relationship existing between intra-oral fluoride levels and dental caries experience. The two main types of slow-release devices - copolymer membrane type and glass bead - are addressed in the present review. A substantial number of studies have demonstrated that these devices are effective in raising intra-oral F concentrations at levels able to reduce enamel solubility, resulting in a caries-protective effect. Studies in animals and humans demonstrated that the use of these devices was able to also protect the occlusal surfaces, not normally protected by conventional fluoride regimens. However, retention rates have been shown to be the main problem related to these devices and still requires further improvements. Although the results of these studies are very promising, further randomised clinical trials are needed in order to validate the use of these devices in clinical practice. The concept of continuously providing low levels of intra-oral fluoride has great potential for caries prevention in high caries-risk groups

Conteúdo de flúor em leites UHT disponíveis comercialmente em Bauru, Brasil

OBJECTIVES: The aims of the present study were to evaluate the fluoride (F) concentrations in whole, defatted and chocolate milks commercially available in Brazil and to estimate the daily F intake from these sources. MATERIAL AND METHODS: F concentrations were determined for 23 brands of milks, after HMDS-facilitated diffusion, using a F ion-specific electrode. Possible F ingestion per kg body weight was estimated, based on suggested volumes of formula consumption, for infants aging 1 to 12 months. RESULTS: F concentrations ranged from 0.02 to 1.6 µg/mL F for all brands analyzed. Whole and defatted milks had the lowest F concentrations, ranging from 0.02 to 0.07 µg/mL. With respect to chocolate milks, three brands had F concentrations above 0.5 µg/mL. Some brands of chocolate milks exceeded the dose regarded as the threshold level for the development of dental fluorosis, without taking into account other sources of fluoride intake. CONCLUSION: The high fluoride concentrations found in some brands of chocolate milks in the present study indicate that many products may be important contributors to the total fluoride intake, reinforcing the need of assaying fluoride content of foods and beverages consumed by small children.OBJETIVOS: Os objetivos do presente estudo foram avaliar as concentrações de flúor (F) em leites integrais, desnatados e achocolatados disponíveis comercialmente no Brasil e estimar a ingestão diária de F a partir destas fontes. MATERIAL E MÉTODOS: as concentrações de F foram determinadas em 23 marcas de leite, após difusão facilitada por HMDS, usando um eletrodo íon-específico para F. A ingestão provável de F por Kg de peso corporal foi estimada, baseando-se em volumes sugeridos de consumo de fórmulas infantis, para crianças entre 1 e 12 meses de idade. RESULTADOS: As concentrações de F variaram entre 0,02 e 1,6 µg/mL para todas as marcas analisadas. Os leites integrais e desnatados apresentaram as menores concentrações de F, variando entre 0,02 e 0,07 µg/mL. Com relação aos leites achocolatados, três marcas apresentaram concentrações de F acima de 0,5 µg/mL. Algumas marcas de leites achocolatados excederam a dose de flúor reconhecida como o limite máximo de exposição a fim de se evitar o desenvolvimento da fluorose dentária, sem se considerar outras fontes de ingestão de F. CONCLUSÃO: As altas concentrações de F encontradas em algumas marcas de leites achocolatados no presente estudo indicam que muitos produtos podem contribuir significativamente para a ingestão total de F, reforçando a necessidade de se avaliar o conteúdo de F em alimentos e bebidas consumidos por crianças pequenas

Fluoride concentrations in industrialized beverages consumed by children in the city of Bauru, Brazil

The increasing consumption of juices, soft drinks and teas among children has increased significantly fluoride ingestion at the age range of risk for development of dental fluorosis. Objective: The purpose of this study was to evaluate fluoride concentrations in some brands of industrialized beverages consumed by children in the city of Bauru, SP, Brazil. Material and Methods: 98 brands of beverages were analyzed, divided into 3 lots, comprising 36, 32 and 30 brands, respectively, for the first, second and third lots. Fluoride concentrations were determined by HMDS-facilitated diffusion, using a fluoride ion-specific electrode (Orion 9409). Results: Fluoride concentrations ranged between 0.04 and 1.76 µg F/mL. It was observed a wide variation in fluoride concentrations among the different brands, as well as the different lots of the same brand. There was no information on fluoride concentrations on the labels of any product. Conclusions: Some of the products analyzed could contribute significantly to the total fluoride intake and, thus, be important risk factors for development of dental fluorosis, which indicates the need of controlling the production of these beverages with respect to fluoride concentration

Enamel subsurface caries-like lesions induced in human teeth by different solutions : a TMR analysis

This study assessed the effectiveness of models for developing subsurface caries lesions in vitro and verified mineral changes by transverse microradiography (TMR). Enamel blocks from permanent (n=5) and deciduous teeth (n=5) were submitted to lesion induction by immersion in demineralizing solutions during 96 h, followed by pH cycles of demineralization (de) and remineralization (re) for 10 days. Two de-/re solutions were tested. Demineralizing solution “A” was composed by 2.2 mM CaCl2, 2.2 mM KH2PO4, 0.05 M acetic acid, with pH 4.4 adjusted by 1 M KOH. Demineralizing solution “B” was composed by 2.2 mM CaCl2, 2.2 mM NaH2PO4, 0.05 M acetic acid and 0.25 ppmF, with pH 4.5 adjusted by 1M KOH. Solution “A” produced cavitated lesions in permanent teeth, whereas solution “B” led to subsurface lesions in deciduous teeth. Solution “B” was then tested in enamel blocks from permanent teeth (n=5) and subsurface lesions were obtained, so that solution “B” was employed for both substrates, and the blocks were treated with slurries of a fluoride dentifrice (1450 ppm F, as NaF, n=5) or a fluoride-free dentifrice (n=5). Solution “B” produced subsurface lesions in permanent and primary teeth of an average (±SD) depth of 88.4μm (±14.3) and 89.3μm (±15.8), respectively. TMR analysis demonstrated that lesions treated with fluoride-free dentifrice had significantly greater mineral loss. This study concluded that solution “B” developed subsurface lesions after pH cycling, and that mineral changes were successfully assessed by TMR.Este estudo avaliou a efetividade de modelos para o desenvolvimento de lesões de cárie subsuperficiais in vitro e verificou alterações minerais por microradiografia transversal (TMR). Blocos de esmalte de dentes permanentes (n = 5) e decíduos (n = 5) foram submetidos à indução de lesão por imersão em soluções desmineralizadoras durante 96h, seguido de ciclos de pH de desmineralização e remineralização por 10 dias. Duas soluções des-/re foram testadas. A solução desmineralizadora “A” foi composta por 2,2 mM de CaCl2, 2,2 mM de KH2PO4, 0,05 M de ácido acético, com pH de 4,4 ajustado por 1 M de KOH. A solução desmineralizadora “B” foi composta por 2,2 mM de CaCl2, 2,2 mM de NaH2PO4, 0,05 M de ácido acético e 0,25 ppmF, com pH de 4,5 ajustado por 1 M de KOH. A solução “A” produziu lesões cavitadas em dentes permanentes, enquanto a solução “B” apresentou lesões subsuperficiais em dentes decíduos. Portanto, a solução “B” foi posteriormente usada em blocos de esmalte de dentes permanentes (n = 5) e lesões subsuperficiais foram obtidas. Portanto, a solução “B” foi empregada para ambos os substratos, sendo metade deles tratada com dentifrício fluoretado e a outra metade com dentifrício livre de flúor. A solução “B” produziu lesões subsuperficiais de cárie com profundidade de 88.4μm (14.3) em dentes permanentes e com 89.3 μm (15.8) em dentes decíduos e TMR demonstrou que lesões tratadas com dentifrício sem flúor tiveram maior perda mineral. Este estudo concluiu que a solução “B” desenvolveu lesões subsuperficiais após o ciclo de pH e as alterações minerais foram avaliadas com sucesso por TMR

Effects of polyphosphates and fluoride on hydroxyapatite dissolution:A pH-stat investigation

AbstractObjectivesThis study investigated the immediate and sustained effect of sodium trimetaphosphate (TMP) and sodium hexametaphosphate (HMP) associated or not with fluoride (F) on hydroxyapatite (HA) dissolution using an erosion-like model, considering as well as the influence of salivary coating.DesignBaseline dissolution rates were determined for HA discs using a pH-stat system. In the first set of experiments, HA discs were treated with 1100μgF/mL, 1% or 8% of HMP, 1% or 8% of TMP and 1100μgF/mL associated with 1% or 8% of HMP or TMP, totaling 9 groups (n=8). In a second phase, HA discs were kept in pooled human saliva at 37°C for 2h before treatment with deionised water and 1100μgF/mL associated with 1% or 8% of HMP or TMP, totaling 5 groups (n=8). The post-treatment dissolution rate was determined from three consecutive 30-min assays. Data were analysed using 2 and 3-way ANOVA followed by Fisher and Holm–Sidak methods, respectively (α=0.05).ResultsAll test solutions promoted reduction in HA dissolution rate when compared to baseline control in the first post-treatment run (p<0.001). However, a synergistic effect was only observed between fluoride and 1% HMP. Moreover, the duration of inhibitory effect was greater when 8% HMP and 1 or 8% HMP associated with F were assessed (p<0.001). The presence of salivary coating led to higher protection for all groups when compared to discs without coating (p<0.001).ConclusionThe reduction of HA dissolution rate, as well as the duration of this effect were influenced by fluoride, type and concentration of phosphate salt and the presence of a salivary coating

New insights into the anti-erosive property of a sugarcane-derived cystatin: different vehicle of application and potential mechanism of action

A new sugarcane-derived cystatin (CaneCPI-5) showed anti-erosive properties when included in solutions and strong binding force to enamel, but the performance of this protein when added to gel formulations and its effect on surface free energy (SFE) requires further studies. Objective: 1) to evaluate the protective effect of gels containing different concentrations of CaneCPI-5 against initial enamel erosion (Experiment 1); and 2) to analyze the SFE (γS) after treating the enamel surface with CaneCPI-5 solution (Experiment 2). Methodology: In Experiment 1, 75 bovine enamel specimens were divided into five groups according to the gel treatments: placebo (negative control); 0.27%mucin+0.5%casein (positive control); 0.1 mg/mL CaneCPI-5; 1.0 mg/mL CaneCPI-5; or 2.0 mg/mL CaneCPI-5. Specimens were treated with the gels for 1 min, the AP was formed (human saliva) for 2 h and the specimens were incubated in 0.65% citric acid (pH=3.4) for 1 min. The percentage of surface hardness change (%SHC) was estimated. In Experiment 2, measurements were performed by an automatic goniometer using three probing liquids: diiodomethane, water and ethylene glycol. Specimens (n=10/group) remained untreated (control) or were treated with solution containing 0.1 mg/mL CaneCPI-5, air-dried for 45 min, and 0.5 µL of each liquid was dispensed on the surface to measure contact angles. Results: Gels containing 0.1 and 1.0 mg/mL CaneCPI-5 significantly reduced %SHC compared to the other treatments (p&lt;0.05). Treated enamel showed significantly lower γS than control, without changes in the apolar component (γSLW), but the polar component (γSAB=Lewis acid-base) became more negative (p&lt;0.01). Moreover, CaneCPI-5 treatment showed higher γS - (electron-donor) values compared to control (p&lt;0.01). Conclusions: Gels containing 0.1 mg/mL or 1.0 mg/mL CaneCPI-5 protected enamel against initial dental erosion. CaneCPI-5 increased the number of electron donor sites on the enamel surface, which may affect AP formation and could be a potential mechanism of action to protect from erosion.&nbsp

Perfil de tratamento de urgência de crianças de 0 a 15 anos atendidas no serviço de urgência odontológica da Faculdade de Odontologia de Bauru, Universidade de São Paulo

Dental recordings of 0 to 15-year-old patients assisted at Urgency Dental Service (UDS) from Bauru Dental School, University of São Paulo, in 2001 and 2002, were assessed in order to quantify the number of patients that used the service, to determine attendance patterns, and to record the frequency of different types of dental emergencies and their performed treatment. Data were plotted and submitted to a descriptive statistical analysis. Among the total of patients attended at UDS (6020), 1166 (19.37%) were children, with mean age of 9.24 years. Trauma was the cause for 199 (17.06%) of the recorded urgency visits. It occurred more frequently in children between 0 and 3 years of age (34.42%), and between 7 and 12 years of age (18.12%). The main treatments performed were temporary restoration (33.33%) for coronal fracture, and orientation (24.44%) for luxation. Nontraumatic events were the etiology for 967 (82.92%) of the total urgency diagnosis. The most commonly found nontraumatic diagnosis was dental caries lesions (61.75%), followed by problems of eruption or root resorption (14.27%) and bone or soft tissue lesions (6.51%), among others (17.47%). The most frequent treatments performed for caries lesions were: excavation and temporary restoration (39.39%) when there was no abscess, and coronal opening and dressing (40.95%) for caries lesions with abscess. There was an increasing trend in caries lesions prevalence according to the rising of the age, in contrast to trauma prevalence. Treatment for both situations was done according to the indicated protocol for each case.Prontuários odontológicos de crianças de 0 a 15 anos de idade atendidas no Setor de Urgência Odontológica (SUO) da Faculdade de Odontologia de Bauru, Universidade de São Paulo, em 2001 e 2002, foram avaliados a fim de se quantificar o número de pacientes que utilizaram o serviço, determinar os padrões de atendimento e relatar a freqüência de diferentes tipos de emergências odontológicas e dos tratamentos realizados. Os dados foram tabulados e submetidos a uma análise estatística descritiva. Do total de pacientes atendidos no SUO (6020), 1166 (19,37%) eram crianças, com média de idade de 9,24 anos. Lesões traumáticas foram responsáveis por 199 (17,06%) do total de visitas de emergência. Isso ocorreu mais freqüentemente em crianças entre 0 e 3 anos (34,42%), e entre 7 e 12 anos (18,12%). Os principais tratamentos realizados foram restauração temporária (33,33%) para fratura coronária, e orientação (24,44%) para luxação. Eventos não-traumáticos foram responsáveis por 967 (82,92%) do total de diagnósticos de emergência. O diagnóstico mais comumente encontrado foi cárie dentária (61,75%), seguida por problemas de irrupção e reabsorção óssea (14,27%) e lesões em tecido duro ou mole (6,51%), entre outros (17,47%). Os tratamentos realizados com maior freqüência para os casos de cárie foram: escavação e restauração temporária (39,39%) quando não havia abscesso, e abertura coronária e curativo (40,95%) para cáries com abscesso. Houve uma tendência para o aumento na prevalência de cárie com a idade. O oposto foi observado para traumatismo dentário. O tratamento para ambos estava de acordo com o preconizado para este tipo de serviço

Fluoretação da água de abastecimento público e prevalência de fluorose dentária em bairro da periferia de Bauru, SP

OBJECTIVES: The objectives of this study were to assess the fluoride concentration in the public water supply and the prevalence of dental fluorosis in schoolchildren between 7 and 15 years old, living in a peripheral district of the municipality of Bauru. MATERIAL AND METHODS: For this, fifty two water samples were collected on three different days of one week. These samples were analyzed for fluoride by means of the ion-sensitive electrode method (Orion 9609) coupled to a potentiometer (Procyon, model 720). In this method, 1.0 mL of TISAB II (Orion) was added to 1.0 mL of the sample. For the epidemiological survey of fluorosis, 52 schoolchildren of both genders, aged between 7 and 15 were assessed, with prior authorization from their caretakers. Only one person examined the children, after supervised toothbrushing and drying with cotton wool rolls. The TF index was used. RESULTS: The fluoride concentrations in the water samples ranged from 0.62 to 1.20 mg/L, with a mean of 0.9 mg/L. The prevalence of dental fluorosis was 33%, with severity ranging from TF1 to TF4 (Kappa of 0.73 and concordance of 83.33%). CONCLUSIONS: The results from the analysis of water samples indicated a fluoride concentration greater than recommended for Bauru. The fluorosis levels found were higher than expected for a peripheral district, in which water is one of the few sources of fluoride.OBJETIVOS: Avaliar a concentração de flúor na água de abastecimento público e a prevalência de fluorose dentária de escolares entre 7 e 15 anos de idade, residentes em um bairro da periferia de Bauru. MATÉRIAL E MÉTODOS: Foram coletadas 52 amostras de água durante três dias de uma semana e analisadas utilizando-se o eletrodo íon sensível (Orion 9609), acoplado a um potenciômetro (Procyon, modelo 720), com 1,0 mL da amostra à qual foi adicionado 1,0 mL de TISAB II (Orion). Para o levantamento epidemiológico de fluorose foram examinados 52 escolares entre 7 e 15 anos de idade, de ambos os gêneros, mediante a obtenção de autorização prévia dos responsáveis. Somente um examinador realizou os exames após escovação supervisionada e secagem dos dentes com rolos de algodão. O índice utilizado foi o TF, estabelecido a partir do grau máximo verificado em cada indivíduo. RESULTADOS: A concentração de flúor na água variou entre 0,62 e 1,15 mg/L, mantendo uma média de 0,9 mg/L. A prevalência de fluorose dentária verificada foi de 33%, com severidade variando entre TF1 e TF4 (Kappa=0,73 e concordância de 83,33%). CONCLUSÕES: Os resultados da análise das amostras de água indicam uma concentração média de flúor acima do recomendado para Bauru. O índice de fluorose dentária verificado foi maior que o esperado para um bairro da periferia, onde a água é uma das poucas fontes de ingestão de flúor

Effect of fluoride gels with nano-sized sodium trimetaphosphate on the in vitro remineralization of caries lesions

Objective: To evaluate the effects of fluoride (F) gels supplemented with micrometric or nano-sized sodium trimetaphosphate (TMPmicro and TMPnano, respectively) on the in vitro remineralization of caries-like lesions. Methodology: Bovine enamel subsurface lesions (n=168) were selected according to their surface hardness (SH) and randomly divided into seven groups (n=24/group): Placebo (without F/TMP), 4,500 ppm F (4500F), 4500F + 2.5% TMPnano (2.5% Nano), 4500F + 5% TMPnano (5% Nano), 4500F + 5% TMPmicro (5% Micro), 9,000 ppm F (9000F), and 12,300 ppm F (Acid gel). The gels were applied in a thin layer for one minute. Half of the blocks were subjected to pH cycling for six days, whereas the remaining specimens were used for loosely- (calcium fluoride; CaF2) and firmly-bound (fluorapatite; FA) fluoride analysis. The percentage of surface hardness recovery (%SHR), area of subsurface lesion (ΔKHN), CaF2, FA, calcium (Ca), and phosphorus (P) on/in enamel were determined. Data (log10-transformed) were subjected to ANOVA and the Student-Newman-Keuls’ test (p&lt;0.05). Results: We observed a dose-response relation between F concentrations in the gels without TMP for %SHR and ΔKHN. The 2.5% Nano and 5% Micro reached similar %SHR when compared with 9000F and Acid gels. For ΔKHN, Placebo and 5% Nano gels had the highest values, and 5% Micro, 2.5% Nano, 9000F, and Acid gels, the lowest. All groups had similar retained CaF2 values, except for Placebo and Acid gel. We verified observed an increase in Ca concentrations in nano-sized TMP groups. Regarding P, TMP groups showed similar formation and retention to 9000F and Acid. Conclusion: Adding 2.5% nano-sized or 5% micrometric TMP to low-fluoride gels lead to enhanced in vitro remineralization of artificial caries lesions

Effects of long-term fluoride exposure are associated with oxidative biochemistry impairment and global proteomic modulation, but not genotoxicity, in parotid glands of mice

Fluoride has become widely used in dentistry because of its effectiveness in caries control. However, evidence indicates that excessive intake interferes with the metabolic processes of different tissues. Thus, this study aimed to investigate the effects of long-term exposure to F on the parotid salivary gland of mice, from the analysis of oxidative, proteomic and genotoxic parameters. The animals received deionized water containing 0, 10 or 50 mg/L of F, as sodium fluoride, for 60 days. After, parotid glands were collected for analysis of oxidative biochemistry, global proteomic profile, genotoxicity assessment and histopathological analyses. The results revealed that exposure to fluoride interfered in the biochemical homeostasis of the parotid gland, with increased levels of thiobarbituric acid reactive species and reduced glutathione in the exposed groups; as well as promoted alteration of the glandular proteomic profile in these groups, especially in structural proteins and proteins related to oxidative stress. However, genotoxic assessment demonstrated that exposure to fluoride did not interfere with DNA integrity in these concentrations and durations of exposure. Also, it was not observed histopathological alterations in parotid gland