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81.
82.
2006年新疆且末县饮水氟砷及地方性氟中毒调查报告 总被引:1,自引:0,他引:1
目的 了解新疆且末县生活饮用水氟、砷含量及地方性氟中毒(下简称地氟)病情. 方法 2006年5~9月对且末县30个行政村饮用水氟含量和15个行政村水砷含量进行了筛查,对20个行政村降氟、降砷改水工程使用情况进行了调查及水氟、水砷含量检测;地方性氟中毒病情检查3 164人,其中8~12岁学生检查1 242人,成人检查1 922人.结果 且末县56.3%地下水水氟含量偏高,水砷不高,儿童氟斑牙率40.41%. 结论 新疆且末县尚有部分居民患地氟病,应引起重视. 相似文献
83.
Estie Kruger Marc Tennant Kirrilee Smith Jacinta Peachey 《Australasian journal on ageing》2007,26(1):15-20
Objectives: The aim of this study was to assess, in a sample of older rural community‐dwelling Australians, their: oral health status, dental treatment needs, perceived barriers to access dental services and the prevalence and severity of dental anxiety. Methods: A cross‐sectional study of elderly rural Australians. Results: Eighty participants (mean age of 71.7 years) had a mean number of 0.69 (SD 1.6) decayed teeth, 15.72 (SD 13.3) missing teeth and 3.9 (SD 5.4) filled teeth. Forty‐one per cent were edentulous. Xerostomia was reported by 53% of the edentulous and 43% of the dentate. The average Corah Dental Anxiety Scale score was 8.72 (SD 3.8). Prevalence of dental anxiety was 15.6%. Two‐thirds needed dental treatment. Conclusions: Caries experience was lower than that reported in other studies. Reported barriers to use of dental services were long waiting times, lack of perceived dental need and costs. 相似文献
84.
85.
四平市地方性氟中毒监测结果分析 总被引:3,自引:0,他引:3
目的了解病区县及监测点的改水现状及地方性氟中毒病情。方法检测病区县及监测点防氟井使用情况、居民饮水氟含量。采用Dean氏法调查监测点8~12岁儿童氟斑牙患病率;调查监测点16岁以上人群氟骨症患病情况和8~12岁儿童、16岁以上人群尿氟含量。结果病区县79个防氟井中,有29眼(36.71%)完好并可正常使用,其中有20眼(68.97%)饮水氟含量正常。2个监测点饮水氟含量分别为4.78mg/L和0.68mg/L;8~12岁儿童尿氟均值分别为4.53mg/L和1.89mg/L;8~12岁儿童氟斑牙患病率分别为96.88%和33,33%;16岁以上人群氟骨症检出率分别为8.00%和3.67%;氟骨症患者尿氟均值分别为4.39mg/L和2.17mg/L。结论病区县大多数病区饮水氟含量超标,地方性氟中毒防治形势严峻。防氟改水是控制地方性氟中毒的有效方法,应进一步加强。 相似文献
86.
87.
M. Al-lsmaily A. AI-Khussaiby I. G. Chestnutt K. W. Stephen A. AI-Riyami M. Abbas M. Knight 《Community dentistry and oral epidemiology》1996,24(5):362-363
Abstract This study reports the first ever national oral health survey of Omani 12-year-olds. Conducted in October 1993, of the 3,435 children examined, 1,438 (41.9%) were caries-free, although regional variations ranged from 24.8% to 61.9%. Overall, the national DMFT averaged 1.53, the majority of caries experienced being in the form of untreated decay, with occlusal surfaces of first permanent molars being the most commonly involved site. Oral hygiene was poor, only 11% of those examined being scored as plaque-free. 相似文献
88.
Urs Brägger Urs Häfeli Beat Huber Christoph H. F. Hämmerle Niklaus P. Lang 《Clinical oral implants research》1998,9(4):218-224
In most of the studies on long-term radiographic evaluations of crestal bone levels adjacent to dental implants, no baseline radiographs taken immediately post-surgically had been obtained.The aim of this study was to test the reproducibility of a simple radiographic method for linear measurements of changes in bone levels and to evaluate changes in crestal bone levels adjacent co non-submerged ITI® implants 1 year following the surgical procedure. From 128 patients enrolled in a clinical and radiographic longitudinal study 40 patients also had radiographs taken immediately postsurgically. They were, however, not obtained as “identical” images. The radiographs were mounted onto slides and projected on a screen. Mesially and distally from 57 implants triplicate linear measurements of the distance implant shoulder to bone crest were taken, using known dimensions of the implants as internal reference distances. The median difference of 213 (out of 228 possible) duplicate measurements was 0.00 mm (ranging from ?1.72 mm to +1.47 mm when comparing the second co the third reading). Some 81% of the double measurements were within ±0.5 mm and the precision was 0.30 mm. In the immediate postoperative radiographs the median mesial bone level was located at 2.07 mm (distally 2.19 mm) from the implant shoulder. A statistically significant amount of bone loss in the first year was observed mesially (median=?0.78 mm) and distally (0.85 mm)(Wilcoxon matched pairs signed rank test ±0.001). No statistically significant influence of the implant location, the implant length, type of the implant (screw; cylinder) was observed (Kruskal-Wallis P>0.05).The age of the patients was not correlated significantly to the amount of bone loss observed. In conclusion, methodological limitations existed when evaluating linear bone changes in non-identical radiographs using reference dimensions of the implants. The amount of postsurgical bone loss estimated in other studies was confirmed when using an immediate postoperative radiograph as a baseline. 相似文献
89.
A patient with Type I hypoplastic patterned amelogenesis imperfecta, subtype D, presented for prosthodontic evaluation. This article describes the developmental and pathophysiological background of this disease. A clinical report describing the diagnosis, treatment planning, and dental rehabilitation of the patient is reviewed. 相似文献
90.
Gijs A. Kleter Jan J. M. Damen Mark J. Buijs J. M. Ten Cate 《European journal of oral sciences》1997,105(3):278-284
The Maillard reaction between carbohydrate and protein has been proposed as a cause of the browning of carious lesions. The aim of the present investigation was to determine the occurrence of this reaction in bovine dentin collagen in vitro and to establish the effect of the reaction on the proteolytic degradation of bovine dentin collagen in vitro. Slices of demineralized bovine dentin were incubated with 0.2 M glucose or buffer for 10 weeks at 37°C. The formation of initial (furosine) and advanced (pentosidine) products of the Maillard reaction in dentin exposed to glucose was confirmed by HPLC. After reduction with NaBH4 to prevent intermediate Maillard products from further reaction, slices were either degraded with collagenase for fluorescence measurement or incubated with trypsin or pepsin to assess enzymatic degradation. Fluorescence characteristic for the Maillard reaction increased in glucose-exposed slices. Degradation of collagen by pepsin, but not by trypsin, was greatly depressed following glucose pretreatment. This may indicate an altered sensitivity to proteolytic degradation; the Maillard reaction thus has a potential role in caries arrestment. 相似文献