Dental fluorosis of children aged 8-12 in diseased areas in Xi’an City from 2014 to 2018

Abstract

Objective To evaluate the dynamic prevalence of dental fluorosis of children and levels of fluoride in drinking water after improvement of water in Xi’an City, to provide scientific basis for water fluoridation improvement. Methods A total of 35 fluorosis endemic villages were selected as fixed monitor sites in 2014-2018, the ways of water improvement were surveyed, water fluorine content were detected and the prevalence of dental fluorosis in children aged 8 to 12 years were examined. Results Rates of excess fluoride in drinking water from 2014 to 2018 were 22.86%, 14.29%, 11.43%, 11.43% and 8.57%, the difference were significant ( χ 2 = 16.44, P <0.01).The dental fluorosis detection rates of children aged 8 to 12 years were 20.89%, 18.22%, 17.46%, 18.13% and 16.76% in 2014-2018 which showed a obvious descending trend by year ( χ 2 = 10.02, P <0.01). The detection rate of dental fluorosis in children aged 8 and 9 years showed a decreasing trend by year ( χ 2 = 6.53, 4.54, P <0.05). The difference of total rate of dental fluorisis, rate of mild cases rate of moderate-to-severe cases were statistically between the villages without qualified water and the villages with normal fluorine water ( χ 2 = 179.22, 167.93, 10.35, P <0.01). The rate of detection in the villages with the water fluorine exceed standard in 2014-2018 showed a declining trend year by year ( χ 2 = 28.50, P <0.01). The detection rate were significant different across water improvement methods ( χ 2 = 197.76, P <0.01). Detection rate of dental fluorosis decreased from 2014 to 2018 in the areas with municipal water supply showed a decreasing after year ( χ 2 = 12.16, P <0.01). Conclusion The improvement of municipal water supply shows significant effects on water fluorosis control, the detection rate of water fluoride and children’s dental fluorosis in some villages with the other ways of water improvement are still higher than expected, the continuously monitor of fluoride content in water and dental fluorosis in children should be strengthened. 【摘要】 目的 动态监测西安市饮水型氟中毒病区改水后水氟和儿童氟斑牙病情变化趋势,为改水降氟提供科学依据。 方法 2014—2018年在西安市选择 10 个区县的 35 个病区村作为固定监测点,调査改水方式、水氟含量和 8~ 12岁儿童氟 斑牙病情。 结果 2014—2018 年病区村水氟含量超标率分别为 22.86%, 14.29%,11.43%, 11.43%和 8.57%,差异有统计学 意义( χ 2 = 16.44, P <0.01)。各年度间 8~12岁儿童氟斑牙总检出率依次为 20.89%, 18.22%, 17.46%, 18.13%, 16.76%,且呈 逐年下降趋势( χ 2 趋势 = 10.02, P <0.01)。 8,9岁组儿童氟斑牙检出率各年度间比较,呈逐年下降的趋势( χ 2 趋势 值分别为 6.53, 4.54, P 值均<0.05)。水氟含量超标村儿童氟斑牙总检出率、轻度及以下、中度及以上检出率与水氟含量合格村比较,差异 有统计学意义( χ 2 值分别为 179.22,167.93,10.35, P 值均<0.01)。水氟含量超标病区村各年度间的氟斑牙检出率呈逐年 下降趋势( χ 2 趋势 =28.50, P <0.01)。市政供水、低氟井与除氟处理 3 种改水方式儿童氟斑牙检出率差异有统计学意义( χ 2 = 197.76, P <0.01)。市政供水各年度间儿童氟斑牙检出率呈逐年下降趋势( χ 2 趋势 = 12.16, P <0.01)。 结论 市政供水改水降 氟效果显著,其他改水方式仍有部分病区村水氟及儿童氟斑牙检出率未达标,应继续加强改水后水氟含量和儿童氟斑牙病 情监测。