Prevalence of Dental Fluorosis in a City without Fluoridation in its Water Supply: Effect of Sampling

Abstract Objective: To determine the prevalence of dental fluorosis in a population not exposed to fluoridated water and to evaluate the effect of the sampling technique on this measurement. Material and Methods: This observational, cross-sectional and quantitative study was conducted in the city of Mariana, Brazil. The participants were selected based on age, so that they had access to fluoridated dentifrice during the formation of the permanent upper teeth. Based on a nominal survey of schoolchildren aged 14 to 19, a probabilistic sample of 304 such children was clinically examined. Dental fluorosis was measured by the Thylstrup-Fejerskov index. The prevalence of fluorosis identified in a previous study, conducted in 2011 in the same city, using the same methodology but employing convenience sampling, was used as a control to compare the effect of the two sampling techniques. Results: The prevalence of dental fluorosis was 3% based on the probabilistic sampling of the subjects. In the previous study, the prevalence of fluorosis was 7% (p<0.05) based on convenience sampling of the same age group. Both studies detected a Thylstrup-Fejerskov fluorosis index value of 1, corresponding to only a mild degree of dental fluorosis. Conclusion: The convenience sampling technique seems to have affected the prevalence of dental fluorosis identified, with a 4% difference between the two studies. The prevalence of dental fluorosis attributed to the use of fluoridated dentifrice in a population not exposed to fluoridation of the water supply was considered low.

Relação entre estresse percebido e fatores salivares, em mulheres, sob condições basais de estresse / Relationship between perceived stress and salivary parameters in women under regular stress conditions

Objetivo: Verificar a relação entre alguns fatores salivares (fluxo estimulado e não-estimulado, capacidade-tampão e atividade de a-amilase) e o estresse percebido por mulheres em condições basais de estresse. Materiais e Métodos: Selecionou-se 13 voluntárias do gênero feminino, com idade média de 31,4 ± 10,0 anos, alunas do curso de mestrado da Faculdade São Leopoldo Mandic, Campinas, SP. Foi determinado fluxo salivar estimulado (FSE) e não-estimulado (FSNE); capacidade tampão (CT), atividade de a-amilase salivar (AAS) pelo método colorimétrico (Caraway modificado) e índice de estresse percebido (EP) pelo questionário de Cohen. Foi calculado o coeficiente de correlação linear de Pearson (R) entre as variáveis avaliadas (a = 0,05). Resultados: a média ± desvio-padrão dos resultados foi FSE = 1,28 ± 0,39 ml/min; FSNE = 0,39 ± 0,18 ml/min; CT = 4,45 ± 1,53; AAS = 16.324,82 ± 12.001,26 U/dl e EP = 25,62 ± 7,09. Houve correlação positiva e estatisticamente significativa entre o FSE e FSNE (R = 0,5932; p = 0,0325). Não houve correlação entre as demais variáveis. Conclusão: em condições basais de estresse, não houve relação entre o fluxo, capacidade tampão e a atividade de a-amilase salivar com o estresse percebido.(AU)

Aim: To verify the relationship among salivary factors (flow rate, buffer capacity, and alphaamylase activity) and the perceived stress in women, when under basal conditions of stress. Materials and Methods: Fourteen volunteers, students from São Leopoldo de Mandic Faculty, Campinas, SP, females, at an average of 31.4 ± 10.0 years of age, were selected. The salivary flow rate (stimulated and non-stimulated), buffer capacity, activity of salivary alpha-amylase, and the perceived stress (Cohen's questionnaire) were determined. Pearson's coefficient of correlation (R) was applied among the studied factors (a=0.05). Results: Mean ± standard deviation of the results were FSE = 1.28 ± 0.39 ml/ min; FSNE = 0.39 ± 0.18 ml/min; CT = 4.45 ± 1.53; AAS = 16,324.82 ± 12,001.26 U/dl, and EP = 25.62 ± 7.09. A positive, statistically significant correlation between FSE and FSNE (R = 0.5932; p = 0.0325) could be observed. No significant correlations between any other variables could be identified. Conclusion: Under basal conditions of stress, no relationship among salivary flow rate, buffer capacity or alpha-amylase activity, and perceived stress could be observed.(AU)