Perception of dental fluorosis among adolescents living in urban areas of Ethiopia

The objective of the study was to assess the perception of dental fluorosis among adolescents residing in two urban areas in Ethiopia: Addis Ababa (low-fluoride drinking water) and Nazreth (high-fluoride drinking water). Students aged 12-15 years, enrolled in two junior secondary schools in Addis Ababa (n = 161) and two similar schools in Nazreth (n = 177) responded to evaluative statements concerning the appearance of anterior maxillary teeth. Color photographs depicting dental fluorosis (TF score 2, 3, 5 and 7) in maxillary front teeth were used as reference during structured interviews. A majority of the students from Addis Ababa and Nazreth were dissatisfied with the appearance of teeth having TF scores 2 and above. More than 66% of the students from both areas confirmed a need for dental consultation concerning fluorotic teeth with TF > or = [corrected] 2. As compared to their counterparts in Nazreth, children in Addis Ababa felt more embarrassed with TF score 2 and 3 (p < 0.01). TF scores 5 and 7 were found unacceptable both in Addis Ababa and in Nazreth. Students in Addis Ababa, more frequently than their counterparts in Nazreth, believed (erroneously) that dental fluorosis were related to neglect on the part of the child. The present findings confirm that fluorotic teeth constitute a social problem among junior secondary school children residing in low-fluoride as well as in high-fluoride urban areas in Ethiopia and, thereby, corroborate the public concern for safe drinking water.     

滨海新区儿童口腔氟牙症和龋齿流行病学调查

目的 调查滨海新区适龄儿童氟斑牙与窝沟龋的患病情况, 探讨氟斑牙与窝沟龋的关系, 为氟斑牙与窝沟龋的防治提出指导意见。 方法 参考《WHO 口腔健康调查基本方法》（第四版）, 并参照第三次全国口腔流行病学调查方法, 采用横断面调查研究方法对 3 778 名 7～ 9 岁教育水平相近的儿童进行氟斑牙与窝沟龋情况进行调查。结果 样本中氟牙症发生率<10%, 社区氟牙症指数（CFI） 为 0.075。 男学生第一恒磨牙的患龋率和龋均分别是 15.57%、0.46, 而女学生第一恒磨牙的患龋率和龋均分别是 17.41%、0.58。 男女间第一恒磨牙患龋率（χ2=2.345, P＞ 0.05）和龋均无差异。 不同年级组患龋率（χ2=172.576,P＜ 0.05）和龋均有差异,两者均随年级的增长而上升。 结论 天津市经过多年改水降氟工程之后, 在本地区儿童氟斑牙检出率及氟斑牙指数已经呈现下降趋势; 患龋率可能与第一恒磨牙的萌出率存在相关性。     

硒、钼、硼对氟中毒大鼠氟斑牙发生的影响

目的 研究硒、钼、硼对氟中毒大鼠的氟斑牙发生的影响.方法 Wristar大鼠随机分为8组(雌雄各半):硒1组、硒2组、钼1组、钼2组、硼1组、硼2组、氟组、对照组.各组均喂以舍F-45mg/L的蒸馏水及舍不同浓度微量元素的饲料,观察大鼠的一般情况,氟斑牙的发生.结果 硒组体质量增加与对照组接近,优于钼组和硼组(P＜0....     

Fluoride levels and dental fluorosis in two districts in Zimbabwe.

Water from two rural communities in Zimbabwe was analysed for fluoride content and school children in the two districts were examined for dental fluorosis. The survey for fluoride distribution in drinking water and the survey for the prevalence of fluorosis in the two districts were two complementary phases of the same project. In Gokwe District, water from artesian wells was found to contain between 5ppm and 10ppm fluoride ion concentration and as a result, fluorosis was found to be extremely severe in those communities solely dependent on artesian wells. In Chimanimani District, water from hot springs was found to contain five to six ppm fluoride ion concentration and in the catchment area of schools, drinking from hot springs fluorosis was also found to be very severe. In both cases, access to high fluoride water can be linked to administrative decisions taken some thirty years ago. Consideration for the long-term adverse effects of drinking water with excess fluoride had not been taken and now, corrective action will need to incorporate inter-disciplinary expertise.     

氟斑牙儿童甲状腺激素异常与DIO1基因多态性的关系

目的　分析氟斑牙儿童甲状腺激素异常情况及与Ⅰ型脱碘酶（DIO1）基因多态性的关系。方法　2018年6月—2019年6月,在天津市历史水氟区和非水氟区共随机抽取169名7~12岁儿童,检测儿童氟斑牙水平。其中正常儿童（正常组）79名,氟斑牙儿童（氟斑牙组）90名。采集尿样,利用砷铈催化分光光度方法测定尿碘水平。采集血样,化学发光法检测促甲状腺激素（TSH）、游离三碘甲状腺原氨酸（FT3）和游离甲状腺素（FT4）,采用Sequenom SNP分型检测实验测定DIO1中rs2294512位点的多态性,并进行问卷调查。根据DIO1 rs2294512位点的基因型分层后进行多因素Logistic回归分析,研究DIO1基因多态性在氟斑牙与甲状腺激素异常中的作用。结果　相对于正常组,氟斑牙组FT3水平较高,FT4水平较低（P＜0.05）。氟斑牙组FT3过高率达40.0%,高于正常组的21.5%,FT4过高率为3.3%,低于正常组的12.7%（P＜0.05）。DIO1基因AA基因型儿童中,患氟斑牙者FT3较高（OR=6.357,95%CI：1.808~22.347,P=0.004）。结论　DIO1基因rs2294512位点为AA基因型的氟斑牙儿童FT3水平更易升高。     

3种黏结材料对中、重度氟斑牙正畸托槽脱落率的影响

目的观察氟斑牙患者应用不同黏结剂对托槽脱落率的影响,探讨有效的正畸治疗措施。方法 18例氟斑牙患者随机分为3组,A组采用京津釉质黏结剂,B组采用光固化复合树脂黏结剂,C组将氟斑牙表面釉质少量磨除直接贴面黏结,观察各组治疗1个月后的托槽脱落率及不同临床因素的作用。结果 C组氟斑牙患者将氟斑牙表面釉质少量磨除直接贴面黏结的托槽率最低,明显低于A组和B组托槽脱落率,且B组的托槽脱落率明显低于A组,各组间比较,差异均有统计学意义(P<0.05)。各组托槽脱落率男性明显高于女性,差异均有统计学意义(P<0.05或0.01)。儿童和青少年的托槽脱落率明显高于成人,差异均有统计学意义(P<0.05或0.01)。但各组不同牙位间托槽脱落率比较,差异无统计学意义(P>0.05)。结论托槽的黏结是口腔正畸治疗中的重要步骤,将氟斑牙表面釉质少量磨除直接贴面黏结的托槽率效果好,但具有一定的适应证,临床医生应根据患者的不同情况选择合适的黏结剂,以降低托槽的脱落率。     

Widespread risks of dental fluorosis in cotton rats (Sigmodon hispidus) residing on petrochemical waste sites

Fluoride has been identified as a ubiquitous contaminant of soils where petrochemical wastes have been disposed. The purpose of this study was to assess how widespread toxicity risks are to resident vertebrates from chronic exposure to fluoride in the soil of petrochemical-contaminated waste sites. In total, 573 wild cotton rats (Sigmodon hispidus) were examined. The rats that were seasonally collected from 12 contaminated and 12 ecologically matched reference sites across Oklahoma over a 3-yr period. The risks of cotton rats exposed to fluoride were analyzed by means of gross examination, histopathology, and scanning electron microscopy of rat incisors. Cotton rats from reference sites showed no pathologic changes in incisors (98%). In comparison, 46% of cotton rats from contaminated sites had various degrees of dental lesions. The prevalence and severity of dental lesions in cotton rats from contaminated sites were significantly influenced by season. There was a 45% increase in prevalence and a 65% increase in severity of dental lesions from summer to winter. This study demonstrated that cotton rats are very sensitive biomonitors for assessing toxicity risks from soils contaminated with fluoride and that such assessments should consider seasonal influences.     

Beyond冷光美白对四环素牙和氟斑牙的美白效果比较

目的比较Beyond冷光美白技术对轻中度四环素牙及氟斑牙的美白效果。方法选择2010年1月-2012年8月在我院口腔美容科进行牙齿美白的轻中度四环素牙及氟斑牙患者各30例,采用Beyond冷光美白技术对其进行美白,术前及术后用Vita比色板比色,比较美白后即刻、1周(诊室护理后)、6个月、12个月时的美白效果及满意度。结果四环素牙及氟斑牙患者美白后的美白有效率逐渐降低(P<0.05)。氟斑牙颜色接近正常,而氟斑并未完全消失,而患者的满意度一直保持在较高水平;四环素牙患者的满意度下降较多(P<0.05)。结论四环素牙和氟斑牙均可以采用Beyond冷光美白技术进行美白,随着时间的延长,需要进行护理以保持美白效果。     

Studies on neurolathyrism in Ethiopia: Dietary habits, perception of risks and prevention

This study describes the correlation of traditional perceptions and dietary habits with the incidence of neurolathyrism to propose preventive measures. Therefore, 118 households of South Wollo and North Gondar (Amhara Regional State, Ethiopia), of which one third had at least one neurolathyrism affected member, were interviewed.Most of the affected families in this study had one neurolathyrism victim, being predominantly male and of younger age. The incidence among youngsters (boys and girls) was significantly correlated with the consumption of green unripe seeds (eshet), confirming this as a risk factor for developing neurolathyrism. The consumption of other popular grass pea preparations was not age related. Neurolathyrism patients did not attempt any medication as most people knew that neurolathyrism is incurable, but the consumption of grass pea was abandoned after developing the disease. The minority ‘Woito’ tribe was virtually unaffected. They were the only people reporting to consume fish which is rich in amino acids such as methionine and using metallic kitchen utensils in addition to clay pots. This observation points to the correlation between low neurolathyrism incidence and a better balanced diet as well as metallic kitchen utensils, suggesting a new approach for neurolathyrism prevention.     

Evaluation of genetic polymorphisms in MMP2, MMP9 and MMP20 in Brazilian children with dental fluorosis

Recent studies suggested that genetics contribute to differences in dental fluorosis (DF) susceptibility among individuals having the same environmental exposure. This study evaluated if MMP2, MMP9 and MMP20 are expressed during enamel development and assessed the association between polymorphisms in these genes with DF. Mice susceptible and resistant to DF were used to evaluate if MMPs were candidate genes for DF. The animals received fluoride and their enamels were used for immunohistochemistry. Additionally, 481 subjects from a city with fluoridation of public water supplies were recruited. Genotyping was performed using real time PCR. Allele/genotype frequencies were compared between groups. MMP2, MMP9 and MMP20 immunostaining was detected in both animal groups. DF was observed in 22.4% of the subjects. A borderline association was observed in MMP2 (rs243865), MMP9 (rs17576) and in MMP20 (rs1784418) (p = 0.06, p = 0.08 and p = 0.06 respectively). Briefly, MMPs were expressed during enamel maturation and genetic polymorphisms were not associated with DF.     

黄芩防龋作用的实验研究

目的:探讨黄芩提取物的防龋效果及其可能的防龋机制。方法:本实验将标本分为三组,分别采用不同流程处理(第1组:标本→脱矿→浸药→脱矿→检测;第2组:标本→脱矿→浸药→检测;第3组:标本→浸药→脱矿→检测;)乳酸胶体系统致牙本质龋,黄芩提取液、硝酸银、去离子水3组试剂按上述流程处理牙本质标本,在镜下观察处理后的牙本质标本。结果:通过对各组标本的光镜观察发现:第1组去离子水组牙本质小管不规则,而硝酸银组和黄芩组牙本质小管规则。第2组去离子水和黄芩处理后的牙本质小管比第1组规则,硝酸银处理后牙本质小管内有一些硝酸银沉积。第3组黄芩处理后的牙本质小管比去离子水组和硝酸银组规则。结论:黄芩提取物具有一定的防龋能力,其防龋机制可能为黄芩能抑制胶原分解,对脱矿的进一步进行产生影响,从而使牙本质龋的进展受到抑制。同时还发现黄芩可能具有一定的抗脱矿能力。     

Probe on the biomarker to substitute the dental fluorosis for deriving fluoride threshold by animal study

Dental fluorosis had been used for deriving the fluoride acceptable threshold for a long time. However, it was diagnosed on the color or defect degree of tooth, like Dean’s Index, which would be easily influenced by lifestyle, like smoking and drinking tea. Hence, some biomarkers had already tried to assess the fluoride exposure risk with the development of bio-monitor technique, and this paper probed on an available biomarker, which based on a systematic biochemical indicator group relating to different biological function from animal experiment, to take place the old one. The experiment animals had been treated with different levels of NaF, and biochemical indicators were analyzed after three months later. The correlations between changes of biochemical indicators and the exposure levels were analyzed subsequently, and a comprehensive indicator was developed. Both the NOAEL/LOAEL and the Benchmark Dose approach were applied in this article to derive the suitable threshold and for indicator comparison. Our findings indicated that a better dose-response relationship was shown between the comprehensive indicator and exposure dose (R=0.811, R square=0.657) than single indicator (R<0.4, R square<0.2) and Dean’s Index (R=0.737, R square= 0.543). Furthermore, the available threshold of the comprehensive indicator was 1.70 mg/(kg.d) lower than it from dental fluorosis (2.00 mg/(kg.d)) which can protect animals from fluoride damage at rather low exposure level. Even the scientificity of the comprehensive indicator should be verified in further epidemiology research, its advantage can’t be ignored that it cannot only avoid the personally error during clinical diagnosis, but also present a new method to quantize the gap risk from dental fluorosis to skeletal fluorosis for those people cannot be diagnosed by dental fluorosis clinically.     

他汀类药物防治缺血性卒中研究现状与展望

他汀类药物是目前降低低密度脂蛋白胆固醇最有效的药物,其在缺血性卒中防治中有广泛应用。本文就他汀类药物防治缺血性卒中临床证据及他汀类药物的安全性进行了综述。     

渗透树脂联合冷光美白微创治疗氟斑牙的临床疗效

目的观察渗透树脂联合冷光美白微创治疗氟斑牙的临床效果。方法 32例氟斑牙患者,所有患者均在冷光美白微创治疗基础上联合渗透树脂治疗,用VITA比色板记录治疗前后色阶,评价治疗效果;同时对治疗后患者的牙齿敏感度情况进行记录并分析。结果 32例患者经治疗后,牙面白垩色及黄色斑点基本消失,牙面光滑,牙齿色泽均改善明显,效果满意。其中,显效29例,有效3例,无效0例,显效率为90.63%,总有效率为100.00%。在冷光美白微创治疗过程中, 32例患者均出现牙本质敏感的症状,其中轻度敏感19例,中度敏感13例,所有患者均顺利完成整个治疗过程。然而,经过渗透树脂技术治疗后患者均未出现牙本质敏感的症状。结论渗透树脂联合冷光美白微创治疗氟斑牙效果稳定,符合微创理念,值得临床推广使用。     

慢性氟中毒对大鼠内耳毛细胞影响的实验观察

目的探讨慢性氟中毒对大鼠耳蜗毛细胞形态学的改变及其机制。方法借助扫描电镜技术,对60只大鼠进行了实验观察。结果对照组耳蜗内、外毛细胞排列十分规则;低氟组内、外毛细胞都有不同程度的损害,表现为静纤毛粘连、倒伏;高氟组内、外毛细胞的损害严重,出现明显的粘连、倒伏、融合,并可见散在的节段性缺失,以底圈明显。表皮板结构发生不同程度的病变,严重者表皮板穿孔,细胞内容物流出,形成气球样改变。结论慢性氟中毒可对耳蜗毛细胞造成损害,粘连、倒伏、融合及节段性缺失是其主要病理改变,损害与染氟程度呈正相关。     

Relationship between fluoride intake in Serbian children living in two areas with different natural levels of fluorides and occurrence of dental fluorosis

The amount of fluoride present naturally in drinking water is highly variable, being dependent upon the individual geological environment from which the water is obtained. Chronic exposure to exceeding fluoride doses induces set of toxic effects, i.e. fluorosis. The aim of this study was to examine fluoride content in water and in the most frequently used vegetables, potato and bean, grown in two different Serbian regions, i.e. control region (Valjevo) and high naturally occurring fluoride region (Vranjska Banja), and moreover, to correlate estimated daily intake with dental fluorosis occurrence as an adverse effect of fluoride exposure of schoolchildren in Serbia. Study confirmed significant difference in fluoride content in water, potato and bean, consumed by 12-year-old children in two investigated municipalities. Results of the study indicated positive and statistically significant correlation between daily intake of fluoride and dental fluorosis level in the fluorotic municipality of Vranjska Banja (r = 0.61; p = 0.000017). Obtained relationship could be evaluated by means of binary logistic regression analysis, whereas probability for fluorosis occurrence could be predicted using the following equation: fluorosis occurence (%) = (34.852 × C_water − 12.644 × C_potato − 9.362 × C_bean − 7.673) × 100 (Chi-Square (3) = 33.033; p < 0.001).     

Community perceptions and practices about urban malaria prevention and control in Gondar Town, northwest Ethiopia

BACKGROUND: Malaria is becoming a major health problem in urban areas. Community perceptions, knowledge and practices have a major role in the implementation of effective malaria control interventions. Yet little is known about the perceptions and practices of urban community about urban malaria prevention and control. OBJECTIVE: The aim of this study was to assess the knowledge, attitudes and practices of an urban community about malaria prevention and control. METHODS: A community-based cross-sectional study was carried out in three randomly selected malarious Kebeles of Gondar Town during November-December 2004. Knowledge, attitudes and practices were assessed for 489 household members > or =18 years old. RESULTS: Almost all respondents knew about malaria and recognized it as one of the major health problems of the community. About 58% knew that malaria could be transmitted from one person to another, and most (97.2%) associated malaria with the bite of mosquito. The most frequently reported symptoms of malaria included fever (96.3%), chills and shivering (96.3%), headache (96.1%), loss of appetite (92.2%) and joini pain (90.2%). Knowledge about the names of the currently used antimalarials, sulfadoxine-pyrimethamine (90.4%) and chloroquine (81.6%), was high. About 39% of the total 163 surveyed households possessed at least one mosquito net; of these, 55 (83.7%) possessed one, 7 (11%) had two and 2 (2.3%) possessed three. Most respondents practiced draining stagnant water (46.3%) and clearing vegetation (43.3%) for malaria prevention. CONCLUSIONS: Although considerable gaps were observed between knowledge and practices of malaria prevention and control methods, community knowledge, attitudes and practices on the cause, treatment and prevention of the disease were encouraging. Since malaria is identified as a major health problem, the use of personal protection methods such as insecticide treated mosquito nets should be encouraged through increasing access to it.