| Objectives:To explore the effects of dietary nutrients to the relationship between water fluoride and dental fluorosis.Methods:The multi-stage random sampling method was used to select survey object. Six provinces with high concentration of water fluoride was selected at the first stage.They were eastern region Jiang Su, Shandong, the central region Hebei, Anhui, Henan and the western region Shanxi provience. Randomly chosen six villages from these provinces where water fluorine content in the< 0.8,0.8～,1.0 ～.1.2～,1.5～,2.0-mg/L(water supply point) for survey spot, a total of 29 spots was chosen. Selected the children aged 8 to 12 in the school which drinking the same water or using the same water supply system with each investigation spot as survey object. In the sampled villages,10% of students aged from 8 to 12 have been sampled as respondents of dietary investigation. Investigation methods contain field dietary sampling, dietary sample weighing and registration, face to face questionnaire survey and fluorine test in laboratory. Use excel to collect questionnaire and laboratory test data then establish the database.The statistical methods such as chi-square and rank are used to describe the distribution of water fluoride concentration, dietary fluoride content and dental fluorosis prevalence in the different age and gender. Using single factor and multiple factors unconditioned logistic regression to establish a model and explore the relationship between dietary nutrition intake, water fluoride concentration and dental fluorosis. The Statistical analysis software have been excused was excel. statal2.1, sas9.3.Results:1. There are 255 children aged 8～12 in this investigation total.72 dental fluorosis children had been checked out. The dental fluorosis prevalence rate was 28.24%, including 126 boys and the 129 girls. Boy’s rate (30.01%) is equal to girl’s rate (25.40%)(x2=0.99, P-0.32). The rates between different aged children had no statistical difference (x2=4.38, P=036).2. The dietary nutrition survey showed that children’s dietary calcium, vitamin A, vitamin C intake is much lower than the corresponding reference nutrient intakes (RNIs).However, dietary magnesium and protein intake attained RNIs level, dietary iron and vitamin E intaken were fhigher than RNIs.3. The average daily intake of dietary magnesium of dental fluorosis children was below the non-dental fluorosis children (Z2=5.31,P=0.02).the intake of Dietary calcium in non-dental fluorosis children below the dental fluorosis children But there was no statistically sign ificant difference (x2=3.55, P=0.06).4. The Water fluoride concentration and average daily dietary fluorine intake between different aged children had no statistical difference.,So as the sex. Water fluoride concentration and the total fluorine intake had a linear correlation (t= 23.26, P< 0.0001). Water fluoride concentration and the average daily dietary fluorine intake had a linear correlation (t= 3.93, P< 0.0001). R2=0.097, adjust R2= 0.094.5. Univariate logistic regression analysis showed dental fluorosis is associated with the dietary intake of calcium, magnesium(x2=5.873,P=0.015;x2=7.347, P=0.007). multiple factors logistic regression analysis showed that the dental fluorosis prevalence rate is negatively related to dietary magnesium, and is positive correlation related to dietary iron.6. we using Water fluoride concentration, dietary nutrition intake as the independent variable, whether of dental fluorosis as the dependent variable, logistic regression model for the Logit (p)=-1.476+0.824×sf+0.048 × fe-0.005 ×mg was fitted.(sf:water content;fe: dietary iron intake;mg:dietary magnesium intake).dietary magnesium, dietary iron is relate the dental fluorosis incidence.the whole model has statistical significance (x2= 27.32, p< 0.0001).7. According to different levels of dietary nutrients condition the association between water fluoride concentration and dental fluorosis prediction probability is different, as dietary magnesium-calcium intake reduced (graphics from down to up), the predicted probability of dental fluorine at the same water fluoride concentration risen, showed the dietary calcium and magnesium has a negative effect of dental fluorosis prediction probability. For example when Water fluoride concentration is 1.5 mg/L, the prediction probability (on both ends of the curve on the vertical axis) of dental prediction probability changed about 15% of total.Conclusion:1. In this survey, All the cases were mainly mild dental fluorosis. Moderately and severely dental fluorosis was no more than a third.2. The Water fluoride concentration and daily dietary fluorine intake as two sources of the total fluoride intake can be seemed indepentedly although the correlation between water fluoride concentration and dietary fluoride intake had statistically significance. But there were other sources of daily dietary fluorine.3. Dietary magnesium, dietary iron had influence on the occurrence of dental fluorosis. Dietary magnesium and dietary calcium may be the protective factors of dental fluorosis. Dietary iron may be the harmful factors of dental fluorosis. |
PDF Full Text Request