Stockton Lawrence W, Tsang Susan T
Department of Restorative Dentistry, Faculty of Dentistry, University of Manitoba, Winnipeg, Manitoba.
J Can Dent Assoc. 2007 Apr;73(3):255.
Composite restorations are more frequently being placed with margins apical to the cementoenamel junction. However, margins within dentin are prone to microleakage. The purpose of this in vitro study was to evaluate various restorative procedures in terms of their ability to reduce microleakage in posterior composite restorations with gingival margins within dentin. We also examined the effect of staining time on microleakage.
Mesio-occlusal and disto-occlusal preparations were made in 50 extracted molars. Teeth were randomly assigned to receive 1 of 5 treatments followed by restoration with Z100 composite resin: acid etch (control); Clearfil SE Bond; Prompt-L-Pop; Vitrebond/Scotchbond Multipurpose Plus (closed-sandwich technique); or Geristore/Tenure (open-sandwich technique). After 48 hours of water storage followed by sectioning buccolingually, 1 restoration from each tooth was randomly assigned to either 2- or 4-hour immersion in 50% by weight silver nitrate solution. Restorations were removed and gingival floors analyzed to determine the percentage of surface area stained in each of 3 0.5-mm wide zones.
Repeated measures ANOVA did not reveal statistically significant differences in staining for 2 and 4 hours. Compared with the control group, Clearfil SE bond produced statistically significant reductions in leakage in all 3 zones. Prompt-L-Pop did not reduce leakage significantly except in zone 3 (closest to the pulp). Vitrebond and Geristore both reduced microleakage in zones 2 and 3, but the reduction was greater with the use of Vitrebond.
Both Clearfil SE Bond and Vitrebond in a closed-sandwich technique were effective methods for reducing microleakage within dentin.
复合树脂修复体越来越多地放置在牙骨质釉质界根尖侧的边缘。然而，牙本质内的边缘容易发生微渗漏。本体外研究的目的是评估各种修复程序在减少牙本质内牙龈边缘的后牙复合树脂修复体微渗漏方面的能力。我们还研究了染色时间对微渗漏的影响。
在50颗拔除的磨牙上制作近中咬合面和远中咬合面预备。将牙齿随机分为5种治疗方法之一，然后用Z100复合树脂修复：酸蚀（对照组）；Clearfil SE Bond；Prompt-L-Pop；Vitrebond/Scotchbond Multipurpose Plus（封闭三明治技术）；或Geristore/Tenure（开放三明治技术）。在水储存48小时后进行颊舌向切片，从每颗牙齿中随机选取1个修复体，分别在50%重量的硝酸银溶液中浸泡2小时或4小时。取出修复体，分析牙龈底部，以确定3个0.5毫米宽区域中每个区域的染色表面积百分比。
重复测量方差分析未显示2小时和4小时染色有统计学显著差异。与对照组相比，Clearfil SE bond在所有3个区域的渗漏均有统计学显著降低。Prompt-L-Pop除了在区域3（最接近牙髓）外，没有显著降低渗漏。Vitrebond和Geristore都减少了区域2和3的微渗漏，但使用Vitrebond时减少幅度更大。
Clearfil SE Bond和Vitrebond采用封闭三明治技术都是减少牙本质内微渗漏的有效方法。
