Prime ＆ Bond NT粘结剂对银汞合金充填微渗漏及密合度的影响

目的探讨Prime&Bond NT粘结剂对银汞合金充填微渗漏及密合度的影响.方法前磨牙120个,随机分为2组,分别进行微渗漏实验及密合度实验.每组中又分为空白对照组、EDTA组和实验组.每个样本的中央制备深3 mm、直径2 mm的窝洞,空白对照组进行常规银汞合金充填;EDTA组使用10%EDTA处理窝洞后充填银汞合金;实验组在EDTA组的处理基础上采用Prime&Bond NT粘结剂进行粘结性充填,分别采用染料渗入法及扫描电镜进行微渗漏及密合度观察.结果实验组的微渗漏率及洞壁与充填体间的间隙明显小于EDTA组(P<0.01);EDTA组又小于空白对照组(P<0.05).结论Prime&Bond NT粘结剂能增加洞壁与银汞合金充填体间的密合度,减少微渗漏.     

树脂粘结剂对银汞合金充填微渗漏的影响

目的 研究树脂粘结技术对银汞合金充填时微渗漏的影响。方法 以银汞合金充填作对照,对应用粘结剂后再完成的银汞合金充填进行了微渗漏试验和扫描电镜观察。结果 用粘结剂组粘结剂与窝洞壁,粘结剂与银汞合金均有良好的粘结。对照组合金钱怀沿壁间可见明显间隙。结论应用树脂粘结剂可增加充填体与洞壁密合度,明显减少银汞合金充填微渗漏。     

不同窝洞处理剂对银汞合金充填微渗漏的影响

目的：探讨减少银汞合金充填后边缘微渗漏的有效方法。方法：选择无龋的离体磨牙４８个，随机分为４组，每个牙分别制面洞、颊面颈１／３洞。比较几种窝洞洞壁处理后对微渗漏的影响。结果：银汞合金充填１个月后，１０％ＥＤＴＡ处理窝洞组、１０％ＥＤＴＡ加护洞漆组与空白组之间的边缘微渗漏无明显差异，而含３％ＦｅＣｌ３的１０％枸橼酸（１０－３液）处理加银汞合金粘结剂组则明显减少微渗漏。结论：离体牙实验证明银汞合金粘结修复可明显减少银汞合金充填术后的微渗漏     

银汞合金充填应用树脂粘结剂的作用研究

目的：研究银汞合金充填时应用树脂粘结剂的作用。方法：进行染料渗透试验和扫描电镜观察。结果：使用粘结剂组染料渗漏的例数少、程度轻，差异性非常显著；扫描电镜可见粘结剂与洞壁和银汞合金均有较好粘结，密合度好。结论：银汞合金充填应用树脂粘结剂可以明显减少微渗漏和增加洞壁密合度。     

应用有机粘结剂减小银汞合金充填体边缘微漏的实验研究

银汞合金充填体与牙齿之间的微漏是临床修复中最令人困扰的问题之一。本研究采用染料逆扩散法,研究了两种类型的银汞合金(普通屑形及高铜球形银汞合金)在应用与不应用粘结剂(Clearifil)的条件下的边缘微漏。结果表明,在银汞合金充填窝洞之前,应用有机粘结剂有效地减小充填体的边缘微漏,涂一层与涂两层粘结剂,其减小微漏的程度无显著差别。高铜球形与普通屑形银汞合银,在应用与不应用粘结剂情况下,边缘微漏无显著差别。     

牙本质粘结剂对洞缘封闭和洞壁密合度的影响

为了解牙本质粘结剂与牙本质及牙骨质的粘结性能,选用三种牙本质粘结剂,配合复合树脂,对新鲜拔除之前牙和前磨牙进行充填粘结试验。通过染料溶液浸泡和扫描电镜观察,对材料的洞缘封闭和洞壁密合度作比较评价。结果是有釉质的洞缘封闭最好,牙本质洞缘封闭较差,牙骨质的洞缘封闭最差。比较几种牙本质粘结剂,洞缘封闭性能无显著差异。     

复层粘结剂对银汞合金粘结效果的实验研究

目的 应用剪切力测试和扫描电镜观察,探讨复层粘结剂对银汞粘结力的影响。方法 选１８颗健康新鲜的恒磨牙牙冠部,中央制备直径３ｍｍ圆柱形洞,分为Ａ、Ｂ、Ｃ３组,Ａ组和Ｂ组的洞壁分别涂２层及１层Ｓｃｏｔｃｈ－ｂｏｎｄ ＭＰ Ｐｌｕｓ粘结剂后充填银汞合金,Ｃ组仅填入银汞合金。２周后经冷热循环,测定各组的剪切力。另取完整双尖牙５颗分为３组,做相应处理后用扫描电镜和图像分析仪观测微嵌合层和粘结剂厚度 结果 ３组     

银汞合金粘结修复后充填体边缘微漏的实验研究

目的 研究银汞合金粘结修复填体边缘的微漏情况,方法 将制备洞型后４０颗离体牙随机分二组,一组采用ＢＡＲ法充填银汞,另一组按常规充填银汞,所有标本均进行染料渗透试验,观测染料渗漏情况,并在ＳＥＭ下测量充填体与牙体间的微逢隙宽度,结果 ＢＡＲ组染料渗漏的例数少,程度轻,其微漏明显小于常规组（Ｐ〈０．０１）,扫描电镜观察发现,ＢＡＲ组充填体边缘缝隙宽度明显小于常规组（Ｐ〈０．０１）,结论 银汞合金粘结修     

四种窝洞清洁剂对高铜银汞合金充填密合度的影响

为研究清洁剂处理窝洞对高铜银汞合金充填密合度的影响，测量和比较了用与不用窝洞清洁剂处理，以及用不同的窝洞清洁剂处理对牙体硬组织与充填材料间微泄漏，结果发现微泄漏的程度由大到小依次为：１０％构橡酸（含３％三氯化铁液，简称１０－３液）、２０％草酸钾液、１０％ＥＤＴＡ液、２５％鞣酸液。其中２５％鞣酸、１０％ＥＤＴＡ、２０％草酸钾的微泄漏显著小于空白对照组和１０－３液组。表明充填前采用合适的清洁剂处理，能提高高铜银汞合金充填的密合度。提示２５％鞣酸、１０％ＥＤＴＡ液为良好的窝洞清洁剂。     

玻璃离子水门汀粘接银汞合金的微渗漏实验研究

目的通过比较玻璃离子水门汀和银汞合金粘接剂用于银汞合金粘接修复时对微渗漏的影响,探讨临床应用玻璃离子水门汀替代银汞粘接剂的可能性.方法染料渗入试验.结果玻璃离子水门汀能明显降低银汞修复体的边缘渗漏,与空白对照组相比有极显著差异,与银汞粘接剂组相比无统计学差异.结论玻璃离子水门汀粘接银汞合金微渗漏小,可替代银汞粘接剂.     

The sealing of the tooth/amalgam interface by corrosion products

summary A marginal gap exists between the amalgam restoration and the cavity walls. At this interface, there is a constant percolation of fluid containing ions, molecules and bacteria. With time, corrosion products of the amalgam components seal the gap at the amalgam/tooth interface. The corrosion processes for conventional and high copper amalgam and factors affecting the corrosion deposites are reviewed. Better amalgam adaptation to the cavity walls improves the chances of sealing the restoration by corrosion products. The effectiveness of cavity varnish in preventing microleakage until corrosive deposits are formed in discussed.     

A method for sampling the cavity wall/material interface for microbiological culture

A punch method for sampling the cavity wall/material interface for microbiological culture is described. Good correlation was obtained between the recording of micro-organisms by this method and from histological sections.     

Effect of bonded amalgam restorations on microleakage

The purpose of this study was to evaluate quantitatively the effectiveness of adhesive dentin bonding systems in decreasing microleakage at the tooth-amalgam restoration interface. The results indicated that microleakage was significantly reduced when Amalgambond Plus or All-Bond 2 was used as liners in comparison to either Copalite varnish or no linear under amalgam restorations. No significant difference was found between the two dentin bonding systems at all time periods studied.     

The effect of retrograde cavity design on microleakage of amalgam fillings

A phantom head model was modified to simulate as closely as possible the limited access encountered during periapical surgery on maxillary anterior teeth. Extracted human maxillary anterior and mandibular canine teeth were placed in this model in a standardized position for root resection, retrograde cavity preparation and filling with amalgam. Three different designs of retrograde cavities were evaluated: the conventional class 1 cavity, the slot cavity and a previously unreported approach, the funnel cavity. Upon completion of the retrograde filling, the teeth were removed from the model and subjected to microleakage tests by placing radiolabelled lipopolysaccharide in a reservoir created coronal to the retrograde fillings. Leakage was quantified by measurement of radioactivity in scintillation counter. It was found that the retrograde fillings in the funnel cavity leaked significantly less than those in the other two cavity designs. There was no statistically significant difference in leakage between the conventional class 1 and the slot cavities up to the thirtieth day 30.     

Effect of elastic cavity wall and occlusal loading on microleakage and dentin bond strength

OBJECTIVE: This study evaluated the effect of an unfilled-adhesive resin (Adper Single Bond) and a filled-adhesive resin (Adper Single Bond 2) with and without a low viscosity resin (Filtek Flow) as an elastic cavity wall on marginal leakage and dentin microtensile bond strength in Class V composite restorations under unloaded and loaded conditions. METHODS: V-shaped cavities were prepared on the buccal surfaces of 56 premolars lined with unfilled (Groups 1 and 3) or filled (Groups 2 and 4) adhesives with (Groups 3 and 4) and without (Groups 1 and 2) a low viscosity resin and restored with a resin composite. The restored teeth in each group were divided into two sub-groups for unloaded and loaded conditions with 50N loading force for 250,000 cycles parallel to the long-axis of the tooth. Five specimens from each group were cut bucco-lingually 0.7 mm thick and subjected to a dye leakage test for four hours using 2% methylene blue dye. The tested specimens were then trimmed into dumbbell shapes at the gingival margin and subjected to microtensile testing. The remaining two specimens were cut, embedded and observed for resin/dentin interfaces under a scanning electron microscope. RESULTS: For the microleakage test, there were no significant differences in microleakage among the groups on both the enamel and dentin margin. No statistically significant differences were found between microleakage of the loaded and unloaded groups on enamel margins for all materials. There were statistically significant differences between microleakage of the loaded and unloaded groups on the dentin margin for Groups 3 and 4. For the microtensile test, the significant difference was found between Groups 1 and 4 for the unloaded groups. For the loaded groups, there were no significant differences between Groups 1 and 2 and Groups 3 and 4. There were no statistically significant differences in microtensile bond strength between the loaded and unloaded groups except for Group 2. CONCLUSION: The application of filled adhesive or low viscosity resin had no influence on marginal leakage at both the enamel and dentin margin but it had an influence on the microtensile bond strength to dentin of Class V restorations. Occlusal loading significantly increased the degree of marginal leakage at the dentin margin when low viscosity was applied in combination with either unfilled or filled-adhesives, but it decreased dentin bond strength in the group treated with only filled adhesive.