微型银汞合金调制器的临床应用效果分析

目的:比较微型银汞合金调制器与银汞调合器的临床应用效果。方法:随机将需要进行窝洞充填的698颗恒牙分为实验组和对照组,常规备洞、消毒、干燥后用银汞合金充填。实验组采用微型银汞合金调制器调和银汞合金,对照组采用市售电动银汞调合器调和银汞合金。结果:实验组成功率为85.03%,对照组成功率为86.63%,两者无统计学意义(χ2=0.1934,P>0.5)。结论:微型银汞合金调制器调和银汞合金能满足临床要求。     

银汞合金充填致口腔黏膜过敏反应的临床研究

目的分析银汞合金引起口腔黏膜过敏的临床表现和治疗方法。方法收集重庆钢铁集团公司总医院1991年12月至2007年12月共收治的7例银汞合金引起的口腔黏膜过敏患者,对其过敏原因、临床表现及治疗方法进行分析。结果7例过敏患者均由银汞合金充填物中的汞导致,其中有5例临床表现为口炎-皮炎类型,2例为黏膜白色病变类型,去除银汞合金充填物后7例患者均治愈。结论银汞合金充填物致口腔黏膜过敏是由其中的汞引起,去除充填物是治疗的关键。     

银汞充填致口腔粘膜变态反应的临床分析

银汞合金为口腔科常用的充填材料之一,而银汞充填引起口腔粘膜变态反应较少见.我科于1989年～1996年共收治5例,现报道如下:1 临床资料本组5例,男2例,女3例,最大年龄56岁,最小年龄17岁.发病部位均为与银汞合金接触的口腔粘膜处,其中2例伴有四肢及躯干皮肤的红色丘疹,口腔粘膜处病损有4例表现为充血、溃烂,1例表现为白斑伴白色网状病变.发病时间距银汞充填后最短为9小时,最长为2月.5例患者均于双前臂分别行汞、合金粉贴敷试验,贴敷汞处均呈阳性反应.5例患者去除银汞合金后均治愈.     

口腔医务人员职业性汞中毒的防治

银汞合金是口腔科常用的填牙材料。汞(水银)是室温内唯一处于流动状态的金属,在低温下也同样会蒸发。在工作中,如果对汞的保管不当或调合银汞合金时操作不当,手指直接接触以及洒落在地面的余汞,给患者充填龋洞时呼出较高浓度的汞蒸气等,均可通过呼吸道和皮肤进入人体,而引起慢性汞中毒。因此,口腔医务人员对汞中毒的防治,应引起重视。     

国产高银银汞合金调配的体会

目前,银汞合金仍是充填牙体龋洞的理想材料,现就我科近年来使用国产银汞合金充填牙体龋洞的的体会总结如下。 1 材料与器械:粉:国产高银银合金粉;成分为:银(Ag)65％、锡(Sn)29％、铜(Cu)60％、锌(Zn)2％。汞:所含剩余的不挥发物质低于0.02％的纯净汞。调拌器:上海产自动银汞合金调拌器。调拌方法:按示与合金粉的重量比为8:5的所需量放置与调拌器内,调拌15～20s。     

银汞合金桩核修复165颗大面积缺损后牙的应用分析

目的探讨银汞合金桩核在修复后牙牙体大面积缺损的应用疗效。方法对165颗使用银汞合金制作的桩核修复牙体严重缺损的后牙进行1~3年随访,观察其疗效。结果 146颗牙的修复令患者满意。结论银汞桩核作为后牙核系统中的一种方法,具有多种优势,它操作简单,容易完成,而且效果很好,还有一个吸引消费者的优点是和其他昂贵的补牙方法相比较,价格低廉,所以很值得在实践中被推广使用。     

我国医药行业汞污染防治工作的思考

目的 为我国医药行业汞污染防治工作提供参考.方法 分析医药行业中汞和汞化合物的使用和防治工作现状.结果与结论 减少汞和含汞化合物的使用是必然的发展趋势,只有减少使用,加强汞污染的防治,才能减少汞对人体的危害和环境的污染.     

口腔科的汞害防护

银汞合金做为牙科充填材料,虽有久远历史,但至今仍普遍应用。医务人员在长期使用的过程中,对其汞害也逐渐有所认识。汞在室温下就可蒸发并随空气流动,因而在调制、充填、磨除汞合金充填物的过程中挥发的汞即可吸附于诊室的天棚、地板、墙壁、桌椅及器械上,成为经久不断的污染源致使医护人员的慢性中毒。汞的蒸发量与汞的表面积大小成正比,因而     

新型牙体修复用合金--镓合金浅述

银汞合金(amalgam)作为牙体充填材料已有160多年的历史,它具有操作简便、机械强度大等优点,至今在口腔治疗中仍占有重要地位,但是汞对环境的污染,对人体的有害作用也越来越受到人们的重视。近年来,复合树脂在后牙修复中的临床应用逐年增多,但亦存在操作过程复杂,如需酸蚀和使用粘接剂,以及机械性能较弱等缺点而无法取代银汞合金。鉴于此,一种新型充填合金——镓合金作为银汞合金的替代物引起人们的关注。现将镓合金的性能及临床应用综述如下。     

银汞合金对MRI不同扫描序列伪影的影响

目的研究口腔内常用银汞舍金充填材料在磁共振检查时产生的影响及不同检查序列对伪影的影响。方法对临床上常用的银汞合金充填材料制作的全冠做磁共振成像测试,磁共振仪磁感应强度为1．5T,所用序列是梯度回波,加做自旋回波和快速自旋回波。结果银汞合金全冠在磁共振检查时,PDFSE序列伪影最大,T1 FSPGR序列伪影较小,T12 Acq、T2 frFSE序列伪影最小。结论不同扫描序列银汞合金对磁共振成像的影响不同,在进行磁共振检查时选择合适的扫描序列可以最大限度减少伪影的发生。     

The safety of dental amalgam in children

The safety of mercury-containing dental amalgam has been hotly debated for well over a century. Dental exposures from mercury have been suggested as the cause of numerous diseases including multiple sclerosis, autism and many others. Known health effects of mercury exposure include CNS and renal damage. However, these effects have only been shown at occupational or higher levels of exposure, and have not been conclusively shown to be present at levels of mercury exposure consistent with that from dental amalgam fillings. The use of mercury amalgam fillings remains a state-of-the-art treatment for dental caries throughout the world. Although there have been a small number of peer-reviewed reports examining the health effects of dental mercury in children, only very recently have the only randomised, controlled clinical trials (two) of the safety of mercury amalgam been published. The purpose of this review is to discuss the scientific evidence on the safety of the use of mercury-containing dental amalgam as a treatment for dental caries.     

The safety of dental amalgam in children

The safety of mercury-containing dental amalgam has been hotly debated for well over a century. Dental exposures from mercury have been suggested as the cause of numerous diseases including multiple sclerosis, autism and many others. Known health effects of mercury exposure include CNS and renal damage. However, these effects have only been shown at occupational or higher levels of exposure, and have not been conclusively shown to be present at levels of mercury exposure consistent with that from dental amalgam fillings. The use of mercury amalgam fillings remains a state-of-the-art treatment for dental caries throughout the world. Although there have been a small number of peer-reviewed reports examining the health effects of dental mercury in children, only very recently have the only randomised, controlled clinical trials (two) of the safety of mercury amalgam been published. The purpose of this review is to discuss the scientific evidence on the safety of the use of mercury-containing dental amalgam as a treatment for dental caries.     

银汞合金在牙科应用中的不良事件

从银汞舍金的性质和性能等方面阐述了其在牙科中的广泛应用及引起的争议和不良事件；通过检索查询医学文献中报道的牙科使用银汞合金发生不良事件的案例，综合分析其产生不良事件的原因。提出合理化建议。     

Minor changes in serum levels of cytokines after removal of amalgam restorations

Dental amalgam restorations release mercury and silver which is absorbed and distributed in the body. Animal studies have shown that both elements may interfere with the host by activation of the immune system in genetically susceptible strains at exposure levels relevant to those from dental amalgam restorations. The aim of this study was to test the hypothesis of no change over time in concentrations of a number of immune mediators in serum after removal of all dental amalgam restorations in patients with health complaints attributed to their amalgam restorations and compare with a healthy reference group. Twenty patients previously examined at a specialty unit for health complaints attributed to dental materials were included in a clinical trial and had all amalgam restorations replaced with other dental restorative materials. Serum samples were collected before amalgam removal and 3 and 12 months after the removal was finished. Twenty blood donors matched for age and gender were used as comparison group. A fluorescent bead-based (Luminex) immunoassay kit was used to measure cytokines, chemokines and growth factors in serum. At baseline, the patient group had slightly higher values for GM-CSF, IL-6, IL-2R, IFN-alpha, IL-7, and IL-12p40/p70 compared with the reference group. After amalgam removal a decrease towards the median value of the reference group was found for GM-CSF, IL-8, and IL-7. In conclusion, removal of all dental amalgam restorations and replacement with other dental restorative materials was associated with decreased concentrations of Th1-type proinflammatory markers in serum.     

The potential adverse health effects of dental amalgam

There is significant public concern about the potential health effects of exposure to mercury vapour (Hg(0)) released from dental amalgam restorations. The purpose of this article is to provide information about the toxicokinetics of Hg(0), evaluate the findings from the recent scientific and medical literature, and identify research gaps that when filled may definitively support or refute the hypothesis that dental amalgam causes adverse health effects.Dental amalgam is a widely used restorative dental material that was introduced over 150 years ago. Most standard dental amalgam formulations contain approximately 50% elemental mercury. Experimental evidence consistently demonstrates that Hg(0) is released from dental amalgam restorations and is absorbed by the human body. Numerous studies report positive correlations between the number of dental amalgam restorations or surfaces and urine mercury concentrations in non-occupationally exposed individuals. Although of public concern, it is currently unclear what adverse health effects are caused by the levels of Hg(0) released from this restoration material. Historically, studies of occupationally exposed individuals have provided consistent information about the relationship between exposure to Hg(0) and adverse effects reflecting both nervous system and renal dysfunction. Workers are usually exposed to substantially higher Hg(0) levels than individuals with dental amalgam restorations and are typically exposed 8 hours per day for 20-30 years, whereas persons with dental amalgam restorations are exposed 24 hours per day over some portion of a lifetime. This review has uncovered no convincing evidence pointing to any adverse health effects that are attributable to dental amalgam restorations besides hypersensitivity in some individuals.     

Dental metal-induced innate reactivity in keratinocytes

In their paper that is published in Toxicology in Vitro, Rachmawati et al. have recently claimed that in spite of the growing concern about the safety of amalgam, negative reports about the health effects of dental amalgam are still scarce or controversial. Substantial evidence indicates that mercury release from dental amalgam fillings may adversely affect human health. Over the past years, we have shown that exposure to electromagnetic fields (EMFs) can increase the release of mercury from dental amalgam fillings. It is worth mentioning that the results of investigations on the microleakage of amalgam fillings following MRI have confirmed our results. Furthermore, exposure to X-rays as a part of the electromagnetic spectrum has also been linked to increased mercury release from dental amalgam fillings. Considering the explosive rise in human exposure to electromagnetic fields, the role of human exposure to EMF as a key factor in increasing the release of mercury from dental amalgam restorations cannot be simply ignored.     

Legislation and informed consent brochures for dental patients receiving amalgam restorations

In 2008, Norway banned the use of mercury for amalgam restorations. Four states in the United States have developed Informed Consent Brochures for amalgam restorations that must be given to their dental patients. The authors describe a patient who had a large cavity in his left lower molar tooth no.18 that had to be removed by an oral surgeon. When the patient went to the oral surgeon, the surgeon told the patient that he would replace the carious tooth with a gold implant. He was not given an Informed Consent Brochure regarding dental restorative materials. The oral surgeon extracted the carious tooth, replacing the tooth with a supposed gold crown implant. On his yearly dental examination, his dentist took an x-ray of his dental implant and explained that the x-ray could not distinguish whether the implant contained either gold or mercury. Consequently, the dentist referred him to a dental clinic in which the dental implant could be removed without mercury contamination of the patient's neurologic system during the extraction of the implant from the root canal. During the removal of the dental restoration, the dentist found build up expanding into the root canal that had a black color. The crown and underlying tooth were sent to ALT BioScience for analysis. Elemental analysis of the crown and underlying tooth confirmed the presence of mercury in the restoration. The patient should have been given an Informed Consent Brochure by the dentist that described the dental restoration that was used in the dental implant.     

Dental Amalgam and Mercury

Abstract: The mercury concentrations in blood (HgB) and urine (HgU) samples, and in exhaled air (HgAir) were measured in 147 individuals from an urban Norwegian population, using cold vapour atomic absorption spectrometry. The study aimed to estimate the mercury exposure from the dental restorations, by correlating the data to the presence of amalgam restorations. Mean values were HgB=24.8 nmol/1, HgU=17.5 nmol/1 and HgAir=0.8 μg/m³. HgU correlated with HgAir, and both HgU and HgAir with the number of amalgam restorations, amalgam restored surfaces and amalgam restored occlusal surfaces. HgB showed poor correlation to HgU and HgAir and the presence of amalgam restorations. A differentiation of the mercury absorption due to exposure from dental amalgams and from the dietary intake, necessitates measurements of both organic and inorganic mercury in the plasma, and in the erythrocytes. The results suggest that individuals with many amalgam restorations, i.e., more than 36 restored surfaces, absorb 10–12 μg Hg/day.     

Comments on the Article “The Toxicology of Mercury and Its Chemical Compounds” by Clarkson and Magos (2006)

provide their perspectives on the toxicology of mercury vapor and dental amalgam. As scientists who are involved in preparing a German federal guidline regarding dental amalgam, we welcome additional scientific data on this issue. However, Clarkson and Magos do not present all the relevant studies in their review. The additional data provided here show that: (a) Dental amalgam is the main source of human total mercury body burden, because individuals with amalgam have 2–12 times more mercury in their body tissues compared to individuals without amalgam; (b) there is not necessarily a correlation between mercury levels in blood, urine, or hair and in body tissues, and none of the parameters correlate with severity of symptoms; (c) the half-life of mercury deposits in brain and bone tissues could last from several years to decades, and thus mercury accumulates over time of exposure; (d) mercury, in particular mercury vapor, is known to be the most toxic nonradioactive element, and is toxic even in very low doses, and (e) some studies which conclude that amalgam fillings are safe for human beings have important methodogical flaws. Therefore, they have no value for assessing the safety of amalgam.     

The effect of amalgam exposure on mercury- and antibiotic-resistant bacteria

Antibiotic resistance genes can be found on the same mobile genetic elements as genes coding for resistance to metals such as mercury (Hg). Amalgam restorations contain ca. 50% Hg and, therefore, it could be expected that exposure to such dental restorative materials may promote Hg resistance and thereby antibiotic resistance. An in vitro biofilm model was used to grow microcosm dental plaques on enamel or amalgam substrata. The number and proportion of Hg-resistant organisms over time were determined by viable counts. Microcosm dental plaques grown in the presence of amalgam had a higher number and proportion of Hg-resistant bacteria than those grown on enamel. The levels of these Hg-resistant bacteria remained elevated for a period of 48 h, however after 72 h the proportions returned to baseline levels. Of the 42 Hg-resistant bacteria isolated, 98% were streptococci, with Streptococcus mitis predominating. A high proportion of the Hg-resistant isolates (71%) were also resistant to a range of antibiotics, with resistance to tetracycline being encountered most frequently. The results of this in vitro study indicate that placement of amalgam restorations may play a role in promoting the levels of Hg- and antibiotic-resistant bacteria present in the oral cavity.