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1.
Braz J Med Biol Res ; 53(12): e9468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146285

RESUMO

The aim of this study was to evaluate the antimicrobial activity and toxicity of glass ionomer cement (GIC) modified with 5-methyl-2-(1-methylethyl)phenol (thymol) against Streptococcus mutans in silico and in vitro. The antimicrobial activity of thymol on GIC modified with concentrations of 2% (GIC-2) and 4% (GIC-4) was evaluated in a model of planktonic cell biofilm using agar diffusion test, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), dynamic biofilm (continuous flow cell parallel), and bacterial kinetics. Conventional GIC (GIC-0) was used as a control. Thymol toxicity was evaluated in Artemia salina and in silico using Osiris® software. Differences between groups were estimated by analysis of variance, followed by Tukey post hoc test, with a 5% significance level. The results of the agar diffusion test between groups were not significantly different (P≥0.05). Thymol had potential bacteriostatic and bactericidal activity against Streptococcus mutans with respect to planktonic growth, with MIC of 100 µg/mL and MBC of 400 µg/mL. The groups GIC-0, GIC-2, and GIC-4 reduced the biofilm by approximately 10, 85, and 95%, respectively. Bacterial kinetics showed efficiency of the modified GICs for up to 96 h. GIC with thymol was effective against S. mutans, with significant inhibition of the biofilms. Analyses in silico and using Artemia salina resulted in no relevant toxicity, suggesting potential for use in humans. GIC-2 was effective against S. mutans biofilm, with decreased cell viability.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes , Cimentos de Ionômeros de Vidro/toxicidade , Humanos , Teste de Materiais , Óleos Voláteis/farmacologia , Streptococcus mutans
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;53(12): e9468, 2020. graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132501

RESUMO

The aim of this study was to evaluate the antimicrobial activity and toxicity of glass ionomer cement (GIC) modified with 5-methyl-2-(1-methylethyl)phenol (thymol) against Streptococcus mutans in silico and in vitro. The antimicrobial activity of thymol on GIC modified with concentrations of 2% (GIC-2) and 4% (GIC-4) was evaluated in a model of planktonic cell biofilm using agar diffusion test, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), dynamic biofilm (continuous flow cell parallel), and bacterial kinetics. Conventional GIC (GIC-0) was used as a control. Thymol toxicity was evaluated in Artemia salina and in silico using Osiris® software. Differences between groups were estimated by analysis of variance, followed by Tukey post hoc test, with a 5% significance level. The results of the agar diffusion test between groups were not significantly different (P≥0.05). Thymol had potential bacteriostatic and bactericidal activity against Streptococcus mutans with respect to planktonic growth, with MIC of 100 µg/mL and MBC of 400 µg/mL. The groups GIC-0, GIC-2, and GIC-4 reduced the biofilm by approximately 10, 85, and 95%, respectively. Bacterial kinetics showed efficiency of the modified GICs for up to 96 h. GIC with thymol was effective against S. mutans, with significant inhibition of the biofilms. Analyses in silico and using Artemia salina resulted in no relevant toxicity, suggesting potential for use in humans. GIC-2 was effective against S. mutans biofilm, with decreased cell viability.


Assuntos
Humanos , Anti-Infecciosos/farmacologia , Streptococcus mutans , Teste de Materiais , Óleos Voláteis/farmacologia , Biofilmes , Cimentos de Ionômeros de Vidro/toxicidade
3.
Eur Arch Paediatr Dent ; 20(6): 603-607, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31087255

RESUMO

PURPOSE: This study investigated whether the report of mothers about the amount of dentifrice applied on a toothbrush could be a reliable method to estimate the inadvertent use of dentifrices. METHODS: A cross-sectional study was conducted in a randomly selected sample of 334 mothers of children enrolled in public day care centres of a city in the Brazilian northeast. Initially, the mothers chose the figure corresponding to the amount of dentifrice used during their children's daily toothbrushing. Then, they simulated real-life conditions with the toothbrush routinely used to brush the children's teeth. The amount of dentifrice on toothbrush was weighted using an analytical scale. Data were analysed by the Kruskal-Wallis followed by the Dunn test (α = 0.05). RESULTS: The weight of dentifrice on the toothbrush was high (> 0.3 g), mainly considering the categories 'covered only' and 'completely covered' that showed no statistical difference (p > 0.05). The proportion of agreement between the mothers' reports and the weight of dentifrice on the toothbrush was 0.23 (CI 0.18-0.28). CONCLUSION: The mothers' report regarding the amount of dentifrice on the toothbrush by demonstrative figures was not a reliable method to estimate the inadvertent ingestion of fluoride from dentifrices.


Assuntos
Dentifrícios , Brasil , Cariostáticos , Criança , Estudos Transversais , Feminino , Fluoretos , Humanos , Escovação Dentária
4.
Eur J Oral Sci ; 121(5): 457-64, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24028594

RESUMO

Fractional fluoride retention is important during the early years of life when considering the risk of development of dental fluorosis. This study aimed to measure fractional fluoride retention in young children. The objectives were to investigate the relationships between fractional fluoride retention and total daily fluoride intake, age, and body mass index (BMI). Twenty-nine healthy children, up to 4 yr of age, participated; 14 lived in a fluoridated area (0.64 µg ml(-1) of fluoride in drinking water) and 15 lived in a non-fluoridated area (0.04 µg ml(-1) of fluoride in drinking water). The total daily fluoride intake of each child was calculated from the daily dietary fluoride intake and toothpaste ingestion (if fluoride toothpaste was used). Total daily fluoride excretion was measured by collecting voided urine and faeces over a 24-h period, and fractional fluoride retention was calculated by dividing the amount of fluoride retained in the body (total daily fluoride intake minus total daily fluoride excretion) by the total daily fluoride intake. Nine children were excluded from data analysis because of suspected invalid samples. Mean (range) fractional fluoride retention for the remaining 20 children was 0.61 (0.06-0.98). There were no statistically significant correlations between fractional fluoride retention and either age or BMI. However, fractional fluoride retention was correlated with total daily fluoride intake: fractional fluoride retention = 1 - exp (-C × total daily fluoride intake), where C = 28.75 (95% CI = 19.75-37.75). The wide variation in fluoride retention in young children could have important implications when recommendations for fluoride use are being considered.


Assuntos
Cariostáticos/metabolismo , Fluoretação , Fluoretos/metabolismo , Fatores Etários , Índice de Massa Corporal , Brasil/epidemiologia , Cariostáticos/administração & dosagem , Cariostáticos/análise , Criança , Pré-Escolar , Fezes/química , Comportamento Alimentar , Feminino , Fluoretos/administração & dosagem , Fluoretos/análise , Humanos , Lactente , Masculino , Escovação Dentária , Cremes Dentais , Urina/química
5.
Rev. bras. plantas med ; Rev. bras. plantas med;15(4): 513-519, 2013. tab
Artigo em Português | LILACS | ID: lil-695236

RESUMO

O reconhecimento oficial da fitoterapia na odontologia no Brasil veio acompanhado de diversas lacunas na pesquisa científica e na utilização de plantas medicinais, especificamente para espécies vegetais com aplicação nas doenças da cavidade oral. O estado do Amazonas, especificamente a cidade de Manaus, não possui um diagnóstico da aplicabilidade de plantas medicinais nos serviços de atenção Odontológica. Esse estudo propôs realizar um estudo do tipo quali-quantitativo, descritivo e exploratório visando o levantamento da comercialização de plantas medicinais e o estudo etnobotânico para identificação das principais plantas medicinais indicadas e utilizadas nas patologias orais nos atendimentos odontológicos ambulatoriais na cidade de Manaus. Foram entrevistados 197 usuários do serviço odontológico, 150 Cirurgiões-Dentistas, e 47 comerciantes credenciados na prefeitura Municipal de Manaus. A amostragem foi realizada por acessibilidade ou conveniência para os Cirurgiões-Dentistas, enquanto os usuários foram selecionados através de amostragem aleatória simples, e os comerciantes de plantas medicinais foram entrevistados em sua totalidade. Os resultados demonstraram a existência de comercialização de plantas medicinais para patologias orais, destacando-se as seguintes espécies: Pedra ume cãa (Aulomyrcia sphareocarpa), Crajiru (Arrabidae chica), além da planta, sem identificação botânica, conhecida popularmente como Sara tudo. Entre os Cirurgiões-Dentistas e entre os pacientes, apenas 8% e 7,61%, respectivamente, utilizaram plantas medicinais para alterações patológicas orais. Os autores concluíram que as plantas medicinais comercializadas na cidade de Manaus são utilizadas de maneira empírica e que, apesar da Política Nacional de Práticas Integrativas e Complementares (PNPIC), novas políticas públicas de saúde devem inserir plantas medicinais e fitoterápicos de uso oral na rede pública de saúde na cidade de Manaus.


The official recognition of herbal medicine in dentistry in Brazil was accompanied by several gaps in scientific research and the use of medicinal plants, specifically for plant species applied to diseases of the oral cavity. The state of Amazonas, specifically the city of Manaus, does not have a diagnosis of applicability of medicinal plants in Dental care services. This research intended to conduct a qualitative and quantitative-type, descriptive and exploratory study in order to conduct a survey on the commercialization of medicinal plants and an ethnobotanical study to identify the main medicinal plants indicated and used in oral pathologies in outpatient dental care in the city of Manaus. We interviewed 197 users of dental services, 150 dentists, and 47 accredited traders in the Municipality of Manaus. The sampling was performed by accessibility or convenience for surgeon-dentists, while users were selected through simple random sampling, and all traders of medicinal plants were interviewed. The results demonstrated that medicinal plants for oral diseases are commercialized, among which the following species are highlighted: Pedra ume Caa (Aulomyrcia sphareocarpa), Crajiru (Arrabidaea chica), in addition to an unidentified botanical plant popularly known as Sara Tudo. 8% of dentists and 7.61% of patients used medicinal plants for oral pathological changes. The authors concluded that medicinal plants commercialized in the city of Manaus are used empirically, and that, despite the rules from the National Policy on Integrative and Complementary Practices (PNPIC), new public health policies must add medicinal plants and herbal medicines for oral use to the public health system of the city of Manaus.


Assuntos
Humanos , Masculino , Feminino , Etnobotânica/métodos , Odontologia/classificação , Medicamento Fitoterápico , Plantas Medicinais/efeitos adversos
6.
Caries Res ; 46(4): 394-400, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22699417

RESUMO

The aim of this study was to validate the use of fingernail fluoride concentrations at ages 2-7 years as predictors of the risk for developing dental fluorosis in the permanent dentition. Fifty-six children of both genders (10-15 years of age) had their incisors and premolars examined for dental fluorosis using the Thylstrup-Fejerskov index. Fingernail fluoride concentrations were obtained from previous studies when children were 2-7 years of age. Data were analyzed by unpaired t test, ANOVA, and Fisher's exact test when the fingernail fluoride concentrations were dichotomized (≤ 2 or >2 µg/g). Children with dental fluorosis had significantly higher fingernail fluoride concentrations than those without the condition, and the concentrations tended to increase with the severity of fluorosis (r(2) = 0.47, p < 0.0001). Using a fingernail fluoride concentration of 2 µg/g at ages 2-7 years as a threshold, this biomarker had high sensitivity (0.84) and moderate specificity (0.53) as a predictor for dental fluorosis. The high positive predictive value indicates that fingernail fluoride concentrations should be useful in public health research, since it has the potential to identify around 80% of children at risk of developing dental fluorosis.


Assuntos
Cariostáticos/análise , Fluoretos/análise , Fluorose Dentária/etiologia , Unhas/química , Adolescente , Fatores Etários , Dente Pré-Molar/patologia , Biomarcadores/análise , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Feminino , Fluoretação , Fluorose Dentária/classificação , Seguimentos , Previsões , Humanos , Incisivo/patologia , Masculino , Valor Preditivo dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Abastecimento de Água/análise
7.
Caries Res ; 45(6): 568-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22142657

RESUMO

BACKGROUND/AIMS: There are still uncertainties regarding the use of whole and parotid ductal saliva as indicators of chronic exposure to fluoride. This study evaluated the effect of water fluoride concentration, age, gender, geographical area and localization (urban/rural) on fluoride concentrations in whole and ductal saliva. METHODS: Subjects (n = 300) aged 3-7, 14-20, 30-40 and 50-60 years, from five communities (A-E) with different fluoride concentrations in the drinking water, participated in the study. Two samples of drinking water and parotid and whole saliva were collected for each subject and were analyzed for fluoride using appropriate electrode techniques. RESULTS: Mean water F concentrations (±SE, mg/l, n = 60) were 0.09 ± 0.01, 0.15 ± 0.01, 0.66 ± 0.01, 0.72 ± 0.02, and 1.68 ± 0.08 for A-E, respectively. Mean F concentrations (±SE, mg/l, n = 15) ranged between 0.014 ± 0.002 (A, 3-7 years) and 0.297 ± 0.057 (D, 14-20 years) for whole saliva and 0.009 ± 0.001 (C, 30-40 years) and 0.284 ± 0.038 (E, 50-60 years) for parotid saliva. Results of multivariate linear regression analysis showed that geographical area and water fluoride concentration exerted the strongest influence in whole and ductal saliva F concentrations, respectively. CONCLUSION: Therefore, parotid ductal saliva seems to be a more appropriate biomarker of fluoride exposure, and factors like age and localization should also be considered when using this biomarker.


Assuntos
Água Potável/química , Fluoretos/análise , Glândula Parótida/química , Saliva/química , Ductos Salivares/química , Adolescente , Adulto , Análise de Variância , Biomarcadores , Criança , Pré-Escolar , Exposição Ambiental , Feminino , Humanos , Eletrodos Seletivos de Íons , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Adulto Jovem
8.
J Dent Res ; 90(2): 215-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21270463

RESUMO

There has been no comparison between fluoride concentrations in urine and nails of children exposed to different sources of systemic fluoride. The aim of this study was to compare the relationship between fluoride intake with urinary fluoride excretion and fluoride concentrations in fingernails and toenails of children receiving fluoride from artificially fluoridated water (0.6-0.8 mg F/L, n = 25), naturally fluoridated water (0.6-0.9 mg F/L, n = 21), fluoridated salt (180-200 mg F/Kg, n = 26), and fluoridated milk (0.25 mg F, n = 25). A control population was included (no systemic fluoride, n = 24). Fluoride intake from diet and dentifrice, urinary fluoride excretion, and fluoride concentrations in fingernails/toenails were evaluated. Fluoride was analyzed with an ion-selective electrode. Urinary fluoride excretion in the control community was significantly lower when compared with that in the fluoridated cities, except for the naturally fluoridated community. However, the same pattern was not as evident for nails. Both urinary fluoride output and fluoride concentrations in fingernails/toenails were significantly correlated to total fluoride intake. However, the correlation coefficients for fluoride intake and urinary fluoride output were lower (r = 0.28, p < 0.01) than those observed for fingernails/toenails (r = 0.36, p < 0.001), suggesting that nails might be slightly better indicators of fluoride intake at the individual level.


Assuntos
Fluoretos/análise , Fluoretos/farmacocinética , Unhas/química , Análise de Variância , Animais , Biomarcadores , Estudos de Casos e Controles , Criança , Pré-Escolar , Dentifrícios , Fluoretos/urina , Humanos , Leite , Unhas/metabolismo , Cloreto de Sódio na Dieta , Estatísticas não Paramétricas , Abastecimento de Água
9.
J Dent Res ; 89(10): 1106-10, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20651094

RESUMO

Previous studies have indicated that the use of low-fluoride dentifrices could lead to proportionally higher plaque fluoride levels when compared with conventional dentifrices. This double-blind, randomized, crossover study determined the effects of placebo, low-fluoride, and conventional dentifrices on plaque fluoride concentrations ([F]) in children living in communities with 0.04, 0.72, and 3.36 ppm F in the drinking water. Children used the toothpastes twice daily, for 1 wk. Samples were collected 1 and 12 hrs after the last use of dentifrices and were analyzed for fluoride and calcium. Similar increases were found 1 hr after the children brushed with low-fluoride (ca. 1.9 mmol F/kg) and conventional (ca. 2.4 mmol F/kg) dentifrices in the 0.04- and 0.72-ppm-F communities. Despite the fact that the increases were less pronounced in the 3.36-ppm-F community, our results indicate that the use of a low-fluoride dentifrice promotes a proportionally higher increase in plaque [F] when compared with that achieved with a conventional dentifrice, based on dose-response considerations.


Assuntos
Cariostáticos/administração & dosagem , Placa Dentária/química , Dentifrícios/administração & dosagem , Fluoretos/administração & dosagem , Cálcio/análise , Cariostáticos/análise , Cariostáticos/farmacocinética , Criança , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fluoretos/análise , Fluoretos/farmacocinética , Humanos , Placebos , Espectrofotometria Atômica , Fatores de Tempo , Escovação Dentária , Abastecimento de Água/análise
10.
Community Dent Health ; 26(3): 143-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19780354

RESUMO

OBJECTIVES: The aim of this paper is to evaluate the prevalence of enamel defects in infants from a socially and economically poor population and the possible association of these defects with disturbances occurring in the pre-, peri- and postnatal periods of human development. PARTICIPANTS: 117 infants aged between 16 and 18 months old were included in four groups based on gestational age and whether part or full term pregnancy. METHOD: The data were collected in two stages: hospital-based, where gestational and birth records were examined, and home-based, where dental examinations and nutrition were evaluated. The teeth were cleaned and dried with gauze and examined in the open air, avoding direct sunlight in the knee-to-knee position. The enamel defects were coded according to the modified Developmental Defects of Enamel Index. Besides this, body weight and height were considered as anthropometric measures for the evaluation of nutritional status by the National Center for Health Statistics standards. MAIN OUTCOME MEASURES: The data were analyzed using the chi-square and Fisher Exact tests. Besides these tests, logistic regression models were used. RESULTS: The prevalence of enamel defects was 49.6%, higher in the group of male infants (p<0.001). The most frequent type of defect and the most affected surface were, respectively, diffuse opacity (9.5%) and the buccal surface (83.3%), located in the gingival half (6.7%). The logistic regression model showed that educational level, gestational age and intrauterine growth retardation (IUGR), besides a lack of breastfeeding, increased the probability of enamel defects up to level of 5%. CONCLUSIONS: The association between enamel defects and the etiologic factors shown in this study suggest the existence of social influences regarding oral health and teeth development.


Assuntos
Esmalte Dentário/anormalidades , Estado Nutricional/fisiologia , Odontogênese/fisiologia , Anormalidades Dentárias/epidemiologia , Dente Decíduo/anormalidades , Antropometria , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Estudos de Coortes , Comorbidade , Esmalte Dentário/patologia , Inquéritos de Saúde Bucal , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Modelos Logísticos , Masculino , Gravidez , Cuidado Pré-Natal , Prevalência , Fatores Socioeconômicos , Estatísticas não Paramétricas , Anormalidades Dentárias/classificação , Anormalidades Dentárias/patologia , Dente Decíduo/patologia
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;42(8): 707-711, Aug. 2009. tab
Artigo em Inglês | LILACS | ID: lil-520782

RESUMO

Alterations in salivary parameters may increase the caries risk in diabetic children, but, contradictory data on this issue have been reported. The aims of this study were to compare salivary parameters (flow rate, pH and calcium concentration) between healthy and type 1 diabetes mellitus (T1DM) individuals. The sample consisted of 7- to 18-year-old individuals divided into two groups: 30 subjects with T1DM (group A) and 30 healthy control subjects (group B). Fasting glucose levels were determined. Unstimulated and stimulated saliva was collected. The pH of unstimulated saliva was measured with paper strips and an electrode. Calcium concentrations in stimulated saliva were determined with a selective electrode. Group A individuals had inadequate blood glucose control (HbA1C >9%), with means ± SD unstimulated salivary flow rate of 0.15 ± 0.1 mL/min compared to 0.36 ± 0.2 mL/min for group B (P < 0.01). Stimulated salivary flow rate was similar by both groups and above 2.0 mL/min. Saliva pH was 6.0 ± 0.8 for group A and significantly different from 7.0 ± 0.6 for group B (P < 0.01). Salivary calcium was 14.7 ± 8.1 mg/L for group A and significantly higher than 9.9 ± 6.4 mg/L for group B (P < 0.01). Except for elevated calcium concentrations in saliva, salivary parameters favoring caries such as low saliva pH and unstimulated salivary flow rate were observed in T1DM individuals.


Assuntos
Adolescente , Criança , Feminino , Humanos , Masculino , Cálcio/análise , Diabetes Mellitus Tipo 1/fisiopatologia , Saliva/química , Salivação/fisiologia , Estudos de Casos e Controles , Concentração de Íons de Hidrogênio , Taxa Secretória , Saliva
12.
Braz J Med Biol Res ; 42(8): 707-11, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19466283

RESUMO

Alterations in salivary parameters may increase the caries risk in diabetic children, but, contradictory data on this issue have been reported. The aims of this study were to compare salivary parameters (flow rate, pH and calcium concentration) between healthy and type 1 diabetes mellitus (T1DM) individuals. The sample consisted of 7- to 18-year-old individuals divided into two groups: 30 subjects with T1DM (group A) and 30 healthy control subjects (group B). Fasting glucose levels were determined. Unstimulated and stimulated saliva was collected. The pH of unstimulated saliva was measured with paper strips and an electrode. Calcium concentrations in stimulated saliva were determined with a selective electrode. Group A individuals had inadequate blood glucose control (HbA(1C) >9%), with means +/- SD unstimulated salivary flow rate of 0.15 +/- 0.1 mL/min compared to 0.36 +/- 0.2 mL/min for group B (P < 0.01). Stimulated salivary flow rate was similar by both groups and above 2.0 mL/min. Saliva pH was 6.0 +/- 0.8 for group A and significantly different from 7.0 +/- 0.6 for group B (P < 0.01). Salivary calcium was 14.7 +/- 8.1 mg/L for group A and significantly higher than 9.9 +/- 6.4 mg/L for group B (P < 0.01). Except for elevated calcium concentrations in saliva, salivary parameters favoring caries such as low saliva pH and unstimulated salivary flow rate were observed in T1DM individuals.


Assuntos
Cálcio/análise , Diabetes Mellitus Tipo 1/fisiopatologia , Saliva/química , Salivação/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Saliva/metabolismo , Taxa Secretória
13.
Caries Res ; 43(2): 142-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19365118

RESUMO

To evaluate the influence of dentifrice pH and fluoride (F) concentration on F uptake by plaque and nails, two sets of 5- to 6-year-old children were randomly allocated into four groups, according to the type of dentifrice they had been using for 1 year: (1) experimental liquid dentifrice (ELD), 1,100 ppm F, pH 7.0; (2) ELD, 1,100 ppm F, pH 4.5; (3) ELD, 550 ppm F, pH 4.5, and (4) commercial toothpaste, 1,100 ppm F, pH 7.0. In one set of children, nails were clipped. In the second, plaque samples were collected 1 h after the last use of dentifrice. F concentration in plaque and nails was analyzed. Plaque F concentration was significantly lower in group 4 than in groups 1-3. Nail F concentration was significantly higher in group 4, and significantly lower in group 3, than in group 1 or 2. Plaque F uptake was influenced significantly by dentifrice consistency and nonsignificantly by pH and F concentration. Reduction of dentifrice pH did not affect nail F concentration.


Assuntos
Cariostáticos/administração & dosagem , Placa Dentária/química , Dentifrícios/administração & dosagem , Fluoretos/administração & dosagem , Unhas/química , Disponibilidade Biológica , Cariostáticos/análise , Pré-Escolar , Dentifrícios/análise , Relação Dose-Resposta a Droga , Fluoretos/análise , Humanos , Concentração de Íons de Hidrogênio , Fluoreto de Sódio/administração & dosagem , Fluoreto de Sódio/análise , Cremes Dentais/administração & dosagem , Cremes Dentais/análise
14.
Caries Res ; 43(2): 147-54, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19365119

RESUMO

Nails have been suggested as suitable biomarkers of exposure to F, with the advantage of being easily obtained. The effect of water F concentration, age, gender, nail growth rate and geographical area on the F concentration in the fingernail and toenail clippings were evaluated. Volunteers (n = 300) aged 3-7, 14-20, 30-40 and 50-60 years from five Brazilian communities (A-E) participated. Drinking water and nail samples were collected and F concentration was analyzed with the electrode. A reference mark was made on each nail and growth rates were calculated. Data were analyzed by ANOVA and linear regression (alpha = 0.05). Mean water F concentrations (+/- SE, mg/l) were 0.09 +/- 0.01, 0.15 +/- 0.01, 0.66 +/- 0.01, 0.72 +/- 0.02, and 1.68 +/- 0.08 for A-E, respectively. Mean F concentrations (+/- SE, mg/kg) ranged between 1.38 +/- 0.14 (A, 50-60 years) and 10.20 +/- 2.35 (D, 50-60 years) for fingernails, and between 0.92 +/- 0.08 (A, 14-20 years) and 7.35 +/- 0.80 (E, 50-60 years) for toenails. Among the tested factors, geographical area and water F concentration exerted the most influence on finger- and toenail F concentrations. Subjects of older age groups (30-40 and 50-60 years) from D and E showed higher nail F concentrations than the others. Females presented higher nail F concentration than males. Water F concentration, age, gender and geographical area influenced the F concentration of finger- and toenails, and hence should be taken into account when using this biomarker of exposure to predict risk for dental fluorosis.


Assuntos
Cariostáticos/análise , Exposição Ambiental , Fluoretos/análise , Unhas/química , Adolescente , Adulto , Fatores Etários , Biomarcadores/análise , Brasil , Criança , Pré-Escolar , Feminino , Humanos , Eletrodos Seletivos de Íons , Masculino , Pessoa de Meia-Idade , Unhas/crescimento & desenvolvimento , População Rural , Fatores Sexuais , População Urbana , Abastecimento de Água/análise , Adulto Jovem
15.
J Dent Res ; 88(2): 142-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19278985

RESUMO

There has been no comparison of fluoride (F) intake by pre-school children receiving more traditional sources of systemic F. The aim of this study was to estimate the dietary F intake by children receiving F from artificially fluoridated water (AFW-Brazil, 0.6-0.8 mg F/L), naturally fluoridated water (NFW-Brazil, 0.6-0.9 mg F/L), fluoridated salt (FS-Peru, 180-200 mg F/Kg), and fluoridated milk (FM-Peru, 0.25 mg F). Children (n=21-26) aged 4-6 yrs old participated in each community. A non-fluoridated community (NoF) was evaluated as the control population. Dietary F intake was monitored by the "duplicate plate" method, with different constituents (water, other beverages, and solids). F was analyzed with an ion-selective electrode. Data were tested by Kruskall-Wallis and Dunn's tests (p<0.05). Mean (+/- SD) F intake (mg/Kg b.w./day) was 0.04+/-0.01(b), 0.06+/-0.02(a,b), 0.05+/-0.02(a,b), 0.06+/-0.01(a), and 0.01+/-0.00(c) for AFW/NFW/FS/FM/NoF, respectively. The main dietary contributors for AFW/NFW and FS/FM/NoF were water and solids, respectively. The results indicate that the dietary F intake must be considered before a systemic method of fluoridation is implemented.


Assuntos
Cariostáticos/administração & dosagem , Dieta , Fluoretação , Fluoretos/administração & dosagem , Leite/química , Fluoreto de Sódio/administração & dosagem , Animais , Brasil , Cariostáticos/efeitos adversos , Criança , Pré-Escolar , Dieta/efeitos adversos , Fluoretação/efeitos adversos , Fluoretos/efeitos adversos , Fluorose Dentária/etiologia , Fluorose Dentária/prevenção & controle , Análise de Alimentos , Humanos , Peru , Cloreto de Sódio na Dieta/análise , Abastecimento de Água/análise
16.
J Dent Res ; 87(5): 461-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18434577

RESUMO

It has been suggested that fluoride retention in plaque is limited by available binding sites. We determined the effects of fluoridated or placebo dentifrices on plaque and salivary fluoride concentrations [F]s in communities with different water fluoride concentrations (0.04, 0.85, 3.5 ppm). After one week of dentifrice use, samples were collected 1.0 and 12 hrs after the last use of dentifrices. After the use of fluoridated dentifrice, plaque fluoride concentrations were higher at both times, except at 12 hrs in the 3.5-ppm community. Plaque concentrations at 1.0 hr after the use of fluoridated dentifrice increased almost constantly (6.5 mmol/kg), but then decreased approximately 50% at 12 hrs in each community. Unlike previous studies, the present findings suggest that the use of fluoridated dentifrice is likely to increase plaque fluoride concentrations significantly for up to 12 hrs in areas where the water contains fluoride close to 1.0 ppm. As previously reported, plaque fluoride concentrations were directly related to calcium concentrations.


Assuntos
Cariostáticos/farmacocinética , Placa Dentária/metabolismo , Dentifrícios/farmacocinética , Fluoretação , Fluoretos Tópicos/farmacocinética , Análise de Variância , Cálcio/metabolismo , Criança , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Saliva/metabolismo , Fatores de Tempo , Resultado do Tratamento
17.
J Appl Microbiol ; 104(4): 1008-13, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17976174

RESUMO

AIMS: Kluyveromyces lactis was cultured in cheese whey permeate on both batch and continuous mode to investigate the effect of time course and growth rate on beta-galactosidase activity, lactose consumption, ethanol production and protein profiles of the cells. METHODS AND RESULTS: Cheese whey was the substrate to grow K. lactis as a batch or continuous culture. In order to precise the specific growth rate for maximum beta-galactosidase activity a continuous culture was performed at five dilution (growth) rates ranging from 0.06, 0.09, 0.12, 0.18 to 0.24 h(-1). The kinetics of lactose consumption and ethanol production were also evaluated. On both batch and continuous culture a respirofermentative metabolism was detected. The growth stage for maximum beta-gal activity was found to be at the transition between late exponential and entrance of stationary growth phase of batch cultures. Fractionating that transition stage in several growth rates at continuous culture a maximum beta-galactosidase activity at 0.24 h(-1) was observed. Following that stage beta-gal activity undergoes a decline which does not correlate to the density of its corresponding protein band on the gel prepared from the same samples. CONCLUSION: The maximum beta-galactosidase activity per unit of cell mass was found to be 341.18 mmol ONP min(-1) g(-1) at a dilution rate of 0.24 h(-1). SIGNIFICANCE AND IMPACT OF THE STUDY: The physiology of K. lactis growing in cheese whey permeate can proven useful to optimize the conversion of that substrate in biomass rich in beta-gal or in ethanol fuel. In addition to increasing the native enzyme the conditions established here can be set to increase yields of recombinant protein production based on the LAC4 promoter in K. lactis host.


Assuntos
Queijo , Microbiologia de Alimentos , Kluyveromyces/fisiologia , Lactose/metabolismo , beta-Galactosidase/metabolismo , Reatores Biológicos , Eletroforese em Gel de Poliacrilamida , Etanol/metabolismo , Kluyveromyces/enzimologia , Kluyveromyces/crescimento & desenvolvimento , Lactose/análise , Proteínas do Leite/metabolismo , Micologia/métodos , Tempo , beta-Galactosidase/análise
18.
Pesqui Odontol Bras ; 15(2): 87-90, 2001.
Artigo em Português | MEDLINE | ID: mdl-11705203

RESUMO

Several communities in Paraíba have moderate or high levels of fluoride naturally present in the drinking water. A moderate prevalence of dental fluorosis (30-40%) has been observed in some areas where the levels of fluoride are regarded as "optimal" for the region (0.6 ppm). The aim of the present study was to determine the prevalence of dental fluorosis in Princesa Isabel, a city with "sub-optimal" fluoride levels (0.4 ppm). The sample comprised 142 schoolchildren (10- to 15-year-old subjects) randomly selected and examined by means of the TF (Thylstrup & Fejerskov) index. The clinical exams were carried out under indirect natural light by three calibrated examiners. Prior to the examination the teeth were cleaned and dried. Approximately 20% of the subjects examined presented with some degree of fluorosis. Seventy per cent were classified as TF 1 while 30% were classified as TF 2 to 5. The prevalence of fluorosis was higher in male subjects and in premolars. Although the observed prevalence of dental fluorosis was within the expected levels, other sources of systemic fluoride must be controlled. The observed prevalence of dental fluorosis is not a public health problem in this community.


Assuntos
Fluorose Dentária/epidemiologia , Adolescente , Brasil , Criança , Feminino , Humanos , Masculino , Prevalência
19.
Community Dent Oral Epidemiol ; 28(4): 307-13, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10901410

RESUMO

UNLABELLED: Few reports have investigated caries prevalence in rural areas of Brazil. OBJECTIVE: The aim of this study was to observe the caries prevalence (DMFT, DMFS) in 12-year-old children living in rural villages of Paraíba, Brazil with low and moderate fluoride levels in the drinking water and to relate it to sugar intake and oral hygiene. METHODS: One hundred and ninety four children from 13 villages were grouped according to the water fluoride levels: low fluoride (LF, <0.2 ppm F, 96 children) and moderate fluoride (MF, 0.7-1.0 ppm F, 98 children). Caries and oral hygiene (OHI-S) were scored according to WHO criteria. Sugar intake was assessed through interviews. A sub-set of subjects (n=23) from the LF group was re-examined 2 years later. RESULTS: For the LF and MF groups the DMFT (mean, SD) observed was 3.9 (3.7) and 2.5 (2.1) respectively, the DMFS was 9.2 (10.6) and 5.4 (5.7). Both indexes (DMFT, DMFS) showed significant differences (P<0.01, Mann-Whitney U-test) according to the fluoride levels in the drinking water. The mean increment of caries in the sub-set group of subjects was approximately 1.5 surfaces per subject/year. The reported sugar intake was low for both water fluoride groups (P>0.05). In a regression analysis the water fluoride levels, the use of fluoridated toothpaste and oral hygiene index were related to DMFS (R2=0.08, P< or =0.05). CONCLUSIONS: Caries prevalence was lower in MF than in LF rural areas of Paraíba. Caries and sugar intake seems to be lower in rural areas than in urban areas of Paraíba with similar fluoride levels in the drinking water.


Assuntos
Cárie Dentária/epidemiologia , Fluoretação , Brasil/epidemiologia , Criança , Índice CPO , Cárie Dentária/etiologia , Dieta Cariogênica , Sacarose Alimentar/administração & dosagem , Fluoretos/administração & dosagem , Humanos , Higiene Bucal/estatística & dados numéricos , Índice de Higiene Oral , Prevalência , Análise de Regressão , Saúde da População Rural , Estatísticas não Paramétricas
20.
Caries Res ; 33(6): 462-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10529532

RESUMO

This work was based on the hypothesis that fingernail clippings can be used as a biomarker for the subchronic exposure to fluoride. The results provide data on factors that may affect the concentration of fluoride in fingernail clippings as determined with the electrode following HMDS-facilitated diffusion. The following variables had only minor or no effects on the concentrations: (1) the surface area of the clippings (intact, minced or filed into powder) that were placed into the diffusion dishes; (2) soaking in deionized water for up to 6 h; (3) soaking in fluoridated water (1.0 ppm) for 2 h, and (4) removal of the organic material of nails by dry ashing. Fingernail fluoride concentrations were approximately 50% higher than those in toenails. A 1-month period of increased fluoride intake by one of the authors resulted in significant increases in fingernail fluoride concentrations after a lag time of approximately 3.5 months. The fluoride concentrations in fingernail clippings obtained from three groups of Brazilian children were directly related to the concentrations in the drinking water (0.1, 1.6 or 2.3 ppm). The results indicate that: (1) HMDS-facilitated diffusion completely separates fluoride from intact nail clippings, so the need for ashing or other preparative methods is obviated; (2) fingernail fluoride is derived mainly from the systemic circulation, and (3) fluoride intake is reflected by the concentrations in fingernails.


Assuntos
Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Fluoretos/análise , Unhas/química , Análise de Variância , Brasil , Criança , Monitoramento Ambiental/estatística & dados numéricos , Dedos , Fluoretos/farmacologia , Georgia , Humanos , Masculino , Unhas/efeitos dos fármacos , Fatores de Tempo , Dedos do Pé , Água/farmacologia
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