Knowledge of Flemish paediatricians about children's oral health – results of a survey

Objective: To examine the knowledge paediatricians have about oral health in children.
Methods: A questionnaire on oral health knowledge was mailed to all members of the Flemish Paediatric Association representing 350 out of 676 Flemish paediatricians. Questions concerned timing of the first dental visit, effects of thumb sucking, fluoride supplements, trauma, fluorosis, mutans streptococci and caries, prevention of dental caries, nursing bottle caries and use of sealants.
Results: Two hundred seventy-six questionnaires (79%) were returned. Of the respondents, 71% said they have had some training on dental topics, and most rely on information brochures to be informed on dental subjects. Parents frequently questioned paediatricians about dental eruption. Paediatricians stated that the first dental visit should be scheduled at the age of 3. Eighty-three percent of the paediatricians stated that thumb sucking was harmful to dentition; 7% regularly prescribed fluoride supplements. Knowledge about fluorosis was moderate. Paediatricians judged community water fluoridation and tooth brushing after consuming erosive drinks as effective. The efficacy of dairy products was underrated. Seventy-three percent of the paediatricians were aware of nursing bottle caries, whereas only 39% were familiar with fissure sealing.
Conclusion: Initiatives are needed to improve knowledge about oral health of physicians involved in preventive health care of children.     

空气氟测定的几个问题的探讨

目的 对空气氟测定方法存在的几个问题进行探讨。方法 用２层都经碳酸氢钠甘油溶液浸渍的超细纤滤纸采集空气氟，对ＴＩＳＡＢ的柠檬酸钠浓度进行选择，滤纸本底值、前处理方法、回收实验和方法现场应用进行研究。结果 选用ｌｍｏｌ／Ｌ柠檬酸钠作ＴＩＳＢＡ测定偏差〈５．２％；经浸渍处理的滤纸本底氟略有升高，但对气态或气溶胶态都能更好地阻留吸收；前处理方法可用于酸浸搅拌成纸浆浸放１ｈ代替４０℃超声１５ｍｉｎ；用煤飞     

The association between osteocalcin gene polymorphism and dental fluorosis among children exposed to fluoride in People's Republic of China

Excessive fluoride intake has been shown to affect dentin and cementum mineralization throughout life. Some studies indicated that a HindIII polymorphism, of osteocalcin (OC) gene, was associated with bone metabolism-related diseases. Therefore, it is possible that the variation in OC genotypes will be associated with dental fluorosis (DF) status and/or serum caciotropic hormone level. A case-control study was conducted among children aged 8–12 years in Henan Province, PR China to investigate the association between dental fluorosis, serum calciotropic hormone level, and polymorphisms in the OC gene. HindIII polymorphism in OC gene was genotyped using the PCR-RFLP procedure. OC and calcitonin (CT) level in serum was detected using radioimmunoassay. No significant difference was observed for OC HindIII genotypes among the cases with dental fluorosis, the controls from endemic fluorosis area (EFA) and the controls from non-endemic fluorosis area (NEFA). A significant negative correlation was observed between serum calcium and OC level. No significant relationship was found between OC HindIII polymorphisms and the level of OC and CT. In conclusion, OC HindIII polymorphisms may not be a useful genetic marker for differential risk of dental fluorosis among children in PR China.     

Effects of fluoride on cortical bone remodeling in the growing domestic pig

The purpose of the experiment was to assess the effects of fluoride (F⁻) on the remodeling process of cortical bone. Sixteen pigs, eight experimental animals receiving a supplement of 2 mg F⁻/kg b.w. and eight controls, were studied in individual sties from age 8 to 14 months. At slaughter samples of cortical bone were obtained from the right femur and embedded undecalcified. A new stereologic model based on fluorochrome tissue time markers and isotropic uniform random histologic sections was implied in order to obtain information in three-dimensional terms about dynamic aspects of remodeling.

The rate of remodeling was increased in cortical bone from pigs receiving F⁻ due to an increased activation of new remodeling. A doubling of the length density of resorptive and formative osteons was observed, although the change was statistically significant for the formative osteons only. An 11% decrease in depth of resorption and an 8% decrease in thickness of new bone formed led to a small decrease in the radius of Haversian canals in the fluorotic bone. The porosity of cortical bone was slightly but significantly increased. At formative sites the osteoid thickness and the mineralization rate were not significantly changed by F⁻. It was concluded that the observed changes cannot be explained by F⁻ induced changes in a single cell. Fluoride appears to affect all cells involved in remodeling by direct or indirect mechanisms.     

氟在胎儿组织中的分布研究

本文对31具胎儿组织氟测定观察,氟能透过母体胎盘进入胎儿,胎儿组织氟含量以骨骼中最高,脑组织中最低,并随母体摄氟量和胎龄的增加而增高。     

2002、2003年云南省昭通市昭阳区地方性氟中毒重点监测汇总分析

目的了解昭通市昭阳区燃煤型地方性氟中毒病区防治效果、防治措施落实进度及降氟措施使用管理情况，为调整干预措施提供科学依据。方法采用整群抽样法，调查炉灶、8～12岁儿童氟斑牙、成人氟骨症患病情况，测定辣椒氟、玉米氟、儿童尿氟。结果监测点2002、2003年炉灶使用合格率分别为56．86％、69．57％，玉米氟中位数分别为0．71、1．5mg／kg，辣椒氟中位数分别为6．07、10．56mg／kg，儿童氟斑牙患病率分别为66．67％、25．00％，氟骨症症状与体征检出率分别为36．99％、16．67％。结论随着改炉率的上升和改炉时间的延长，该地区氟中毒的流行得到较好控制．但应加强对病区居民正确使用炉灶的技术指导和降氟炉灶的管理及维修，巩同其除氟效果。     

2008年北京市延庆县地方性氟中毒病情监测分析

目的 了解北京市延庆县地方性氟中毒病区改水降氟措施的效果和发病趋势,为制订防治措施提供依据.方法 2008年,采用分层随机抽样方法在延庆县抽取3个村(谷家营村、簸箕营村和胡家营村),用离子选择电极法检测枯水期和丰水期生活饮用水含氟量:对63名8～12岁儿童和664名16岁以上成人测定尿氟,并检查氟斑牙患病情况.结果 3个村生活饮用水含氟量枯水期为(0.72±0.12)mg/L,丰水期为(0.76±0.18)mg/L.儿童尿氟中位数为1.11 mg/L,范围为0.32-4.15 mg/L;成人尿氟中位数为1.42 mg/L,范围为0.37～4.65 me/L.儿童氟斑牙检出率为23.81%(15/63),氟斑牙指数为0.45;成人氟斑牙检出率为54.97%(365/664),氟斑牙指数为1.70.结论 延庆县生活饮用水含氟量符合国家标准,地方性氟中毒病情有所下降,改水降氟措施效果显著.     

2007年青海省饮茶型氟中毒流行现状与居民饮食结构调查

目的 调查青海省饮茶型氟中毒流行现状,了解居民饮食结构,为预防控制和科研工作提供科学依据.方法 2007年,依据全国<饮茶型地方性氟中毒流行现状调查方案>,结合青海省具体情况对28个县进行调查,每个县抽查3个乡、1个镇,每个乡(镇)抽查2个行政村(居委会),每个村(居委会)抽查50名成人、50名学龄儿童;同时每个县抽查1座寺院,每座寺院抽查成人僧侣50名、儿童僧侣50名.人户调查居民经济收入、饮食结构、砖茶消耗量等.对全部调查对象用Dean法诊断氟斑牙,对同仁、达日、互助县和隆务寺16岁以上成人用200 mA X线机拍片诊断氟骨症,并用调查结果估算全省饮茶型氟中毒的患病人数.结果 ①居民家庭年人均收入大部分在500～<1000元,其次在1000～<3000元;牧业区居民经济收入略高于农业区、半农半牧区和城镇居民.②居民饮食结构,牧业区及半农半牧区主食以面粉为主,其次是糌粑及大米;农业区及城镇主食以面粉为主,其次是大米及糌杷;各地区副食均为肉制品占多数,其次为奶制品,蛋类比例很小.③经常食用的蔬菜为土豆、白菜及青椒,每日食用的家庭占62.82%(6497/10 343);水果以苹果、梨及橘子为主,每月食用不足10次的家庭占75.95%(7856/10 343).④共调查居民61 999人,年砖茶消耗量为153 335 kg,人均2.47 ks;共调查僧侣1001人,年砖茶消耗量为4120 kg,人均4.12 kg.⑤乡镇成人氟斑牙检出率为24.11%(2494/10 343),儿童氟斑牙检出率为24.38%(3012/12 355);成人僧侣氟斑牙检出率为26.13%(203/777),儿童僧侣氟斑牙检出率为39.73%(89/224).⑥乡镇成人氟骨症检出率为15.60%(17/109);成人僧侣氟骨症检出率为4.88%(2/41).⑦氟斑牙患者95%可信限估算总人数为1 084 306～1 134 170人.中位数为1 109 238人;氟骨症患者95%可信限估算总人数为309 177～758 199人,中位数为533 688人.结论 青海省砖茶消耗量较大,饮茶型氟中毒人数多,危害程度比较重;居民饮食结构比较单调,主要靠外地运输.     

山西省临猗县饮水型地方性氟中毒与尿氟关系的研究

目的 了解山西省临猗县饮水型地方性氟中毒的患病情况,探讨氟中毒与尿氟之间的关系,为当地饮水型地方性氟中毒的防治提供依据.方法 2006年在临猗县饮水型地方性氟中毒重、中病区和非病区各选取1个村作为调查点,采用Dean法和离子选择电极法对当地居民进行氟斑牙和尿氟检查,对病区30岁及以上成年人进行前臂正位X线(包括肘与腕)拍片,进行氟骨症患病情况调查.结果 3个地区人群氟斑牙检出率明显不同(X~2=410.945,P<0.01),其中,中病区、重病区氟斑牙检出率分别为92.34%(253/274)、90.09%(291/323),明显高于非病区[23.27%(64/275),X~2值分别为274.927、268.287,P均<0.01].重病区氟骨症检出率[59.75%(141/236)]明显高于中病区[24.76%(52/210),X~2=183.578,P<0.01].3个地区人群尿氟水平差异有统计学意义(H=411.197,P<0.01),其中重病区为(4.69±0.17)mg/L、中病区为(4.86±0.13)ms/L、非病区为(1.75±0.04)mg/L;而氟骨症患病程度与人群尿氟之间呈直线相关关系(r=0.508,P<0.01).结论 山西省临猗县饮水型地方性氟中毒病区氟斑牙、氟骨症患病情况严重,氟骨症患病程度与尿氟水平相关.     

高氟对大鼠甲状腺功能和脑损伤的影响

目的 观察高氟对大鼠甲状腺功能和脑损伤的影响.方法 将36只成年Wistar大鼠按性别和体质量随机分为3组:对照组、高氟组、高氟+甲状腺片组,每组12只,分别饮用自来水(含氟量<5 mg/L),加入100、100 ms/L氟化钠(NaF)的自来水:喂养7个月后高氟+甲状腺片组大鼠另给予0.04%甲状腺片(1.8ml·kg~(-1)·d~(-1))灌胃3周.喂养7个月零3周时,用放射免疫法测定各组大鼠血清TT_3、TT_4;光镜下观察大鼠甲状腺和脑组织形态结构;免疫组化方法检测海马区域NMDAR2B蛋白表达.结果 与对照组[(0.97±0.15)、(84.03±12.45)nmol/L]比较,高氟组大鼠血清TT_3、TT_4明显降低[(0.24 ±0.07)、(15.16±2.08)nmoL/L,P均<0.01];高氟+甲状腺片组与对照组比较,未见明显改变[(1.02 ±0.19)、(85.63±9.55)nmoL/L,P均>0.05],与高氟组相比较,明显增高(P均<0.01).光镜下高氟组可见甲状腺部分滤泡上皮增生、排列紊乱、萎缩,滤泡腔内胶质减少,而高氟+甲状腺片组与高氟组比较,甲状腺滤泡上皮增生程度减轻;高氟组海马神经元细胞肿胀、排列紊乱,高氟+甲状腺片组海马神经元细胞较高氟组肿胀减轻、排列有序.高氟组海马CA1、CA3区NMDAR2B阳性细胞灰度值(167.05±7.31)较对照组(92.53±9.67)和高氟+甲状腺片组(101.66±12.21)明显增高(P均<0.01).结论 高氟可导致成年大鼠甲状腺功能降低、形态改变,并引起大脑病理损害;在高氟损伤基础上给予甲状腺制剂替代后,大鼠甲状腺功能和形态可基本恢复正常,脑组织损伤明显减轻.慢性氟中毒造成的甲状腺功能降低可能是高氟造成脑损伤的另一重要参与因素.