Abstract: Objective To understand the prevalence of dental fluorosis and dental caries among school-age children in high fluoride areas of Lintong District, Xi’an City from 2019 to 2020, and analyze its influencing factors, so as to provide basis for regional prevention and control. Methods Using the stratified cluster sampling method, three primary schools were selected in the high fluoride area of Lintong District, Xi’an City in 2019 and 2020. Students in one class of each grade were selected for oral examination to make statistics on dental fluorosis and dental caries. The influencing factors of dental fluorosis and dental caries among school-age children were analyzed by univariate and multivariate analysis methods. Results There were 1 006 primary school students, including 604 males （60.04%） and 402 females （39.96%）, aged 6-12 years, with an average age of （9.60±1.18） years old. Multivariate Logistic regression analysis showed that urine fluoride ≥2.39 mg/L （OR=16.651） was a risk factor for dental fluorosis in school-age children, while the school-age children whose mother had a high school education or above （OR=0.224） and whose annual family income was ≥ 100 000 yuan （OR=0.058, 0.083） had a lower risk of dental fluorosis. Eating sweets frequently （OR=4.022） was a risk factor for dental caries in school-age children, while the school-age children with urinary fluoride ≥ 1.28 mg/L （OR=0.460, 0.348）, brushing before bed （OR=0.075）, regular oral examination （OR=0.169） and parents’ concern for dental health （OR=0.269） had a lower risk of dental caries. Conclusion The detection rates of dental fluorosis and dental caries among school-age children in high fluoride areas of Lintong District, Xi’an City are relatively high. High urine fluoride is a risk factor for dental fluorosis, and eating sweets frequently is a risk factor for dental caries in school-age children. It is recommended to prevent the above risk factors to reduce the occurrence of dental fluorosis and dental caries.

Key words: High fluoride area, School-age children, Dental fluorosis, Dental caries, Influencing factor