所有选中的牙齿有四个完整的日冕墙壁和正常的根形态。经过仔细的临床检查,牙齿骨折,裂缝,龋齿涉及日冕部分或根,先前endodontically治疗牙齿,牙齿和复杂根形态被排除在研究之外。生物残骸的牙齿清洁的手,然后用超声波标量被彻底清洁。消毒用Chloraxid 2%(2%次氯酸钠、Cerkamed、波兰)和Gluco-Chex 2%(洗必泰digluconate 2%, Cerkamed,波兰)1小时,然后存储在生理盐溶液直到使用[
19,
20.]。所有提取的牙齿的准备过程是所有组织和标准化是由一个操作符。日冕保证访问和工作选择长度在1毫米短点10 k文件退出顶端孔。冠状扩口是通过盖茨Glidden院子里,大小2和3。运河被检测与k的文件(Dentsply Maillefer,瑞士)。ENDO-Prep奶油15% EDTA和10%过氧化脲(Cerkamed、波兰)是用于外套k的文件时使用。连续文件之间,根运河灌溉用5.25%次氯酸钠(Cerkamed、波兰)和使用endoneedle或者生理盐水。整个清洁和形成过程,顶端明显被重演,10 k文件维护。牙齿都是相同的方式检测。涂片层被使用2毫升15% EDTA溶液(Cerkamed、波兰)其次是最后一个充裕2毫升Chloraxid 2%(2%次氯酸钠、Cerkamed、波兰)。 Upon completion of the instrumentation, the canals were dried utilizing absorbent paper points. This process was done to ensure that all canals and especially the point of interest, the canal orifices, were conditioned and prepared with the same working protocol, thereby assuring homogenous conditions for this study. Since the main objective of this research is the coronal microleakage at the level of canal orifices, the experimental teeth were purposefully not obturated with any materials, giving us more room for the neutral red dye. Because of the vast assortment of commercially available materials, for this study, we used the most relevant clinical options. The following materials were investigated: Kavitan Plus, glass-ionomer cement, GIC (PENTRON, Orange, USA); Ionosit, light cured compomer, mGIC (DMG, Hamburg, Germany); brilliant flow, flowable composite (COLTENE, Altstätten, Switzerland); Kerr Premise, packable composite (KERR, Brea, USA); Coltosol F, temporary filling material (COLTENE, Altstätten, Switzerland). Both composites used are made of nanoparticles. The roots of the 20 teeth in the experimental group were cut short 2–5 mm (depending on the pulp chamber morphology) from the level of cementoenamel junction (CEJ) with a tapered fissured diamond bur in a high-speed handpiece under water spray (Figures
3和
4)。这样做是有两个主要原因:为中性红色染料,有足够的空间自由没有染料流经整个根管和潜在泄漏通过横向或附属运河,并确保根他们密封的密封水CEJ易流动的综合指数。
从CEJ Monoradicular牙齿切2 - 5毫米。
从CEJ Pluriradicular牙齿切2 - 5毫米。
在这项研究中使用的牙齿被分成六组。第六组我到V实验组和组是对照组。每个实验小组由四个monoradicular和四个pluriradicular牙齿,而对照组是由一个monoradicular牙齿和一个pluriradicular牙齿。对照组的目的是建立潜在的变色和其他原始齿时变化的生理盐水浸泡在生理盐水对整个实验的持续时间。每组实验测试在一个单独的无菌容器由硬塑料,总量25毫升,用螺丝锁帽;他们从当地的药店购买。为了所有的牙齿完全淹没在等量的生理盐水溶液中,我们测量的体积解决方案需要覆盖最大的牙齿:pluriradicular牙齿从对照组(摩尔)。同样的体积,10毫升,用于所有的样品。首先,我们应用一个密封的所有牙齿,实验和对照组,使用前提可流动的光治疗复合(美国沥青克尔)一起OptiBond独奏+键和蚀刻(37.5%磷酸)系统(克尔、沥青、美国)。牙齿被干,蚀刻CEJ, 15秒,冲洗一个额外的30秒(确保所有蚀刻了)。 After drying lightly, the bonding was applied to all the areas up to the CEJ. After light curing for 20 seconds, the flowable composite was placed and light cured for 40 seconds. The remaining two teeth (one monoradicular and one pluriradicular) were hermetically sealed up to the CEJ and designated as control for each group. These two teeth were in pristine condition and no work was done on them, except for cleaning and disinfection. The role the hermetic seal applied to these particular teeth was to ensure a tight entrapment of the root canal contents. Once the hermetic seal was established, the neutral red dye was placed into the root canal. Endodontic microsponges (LARIDENT, Italy) were used to absorb and contain the neutral red dye inside the root canal and to assure enough firmness to apply the orifice sealing material on top of it, without the materials forcing the dye out of the root canal and into the pulp chamber. The endodontic microsponges were cut into small pieces of about 2 × 2 mm to 4 × 4 mm to accommodate different pulp chamber sizes. With the help of a plastic pipette, one drop of neutral red dye was applied inside the root canal of the experimental teeth and the orifice was covered with a piece of microsponge. The orifice sealing material, according to each testing group, was applied on top of the sponge to create an initial barrier and afterward the bulk of the testing orifice sealing material was applied. After orifice sealing, the teeth were submerged in 10 mL physiological saline solution in individual plastic containers. The containers were shaken for 30 seconds, 2 times per day for 2 weeks. After 2 weeks, a sample of the saline solution was taken from each container and was analysed with the help of a Metertech SP-880 UV/visible spectrophotometer (Metertech, Taipei, Taiwan). Before the analysis of the samples, the peak absorbance point of the tested dye solution was obtained. The peak absorbance point was established at the 540 nm. The saline solution from the container was used for base line (zero absorbance) calibration and the saline solution with one drop of Neutral red dye was used to assess the wavelength of maximum absorbance. As a result, we obtained the peak absorbance point at 540 nm. Finally, the solution from each experimental group was tested (i.e., its absorbance was measured at a wavelength of 540 nm) and the data were recorded. The higher the resulting absorbance value, the weaker the orifice sealing will be.
3所示。结果
所有实验组显示一定程度的染料渗漏到生理盐水。一般来说,monoradicular牙齿少泄漏显示。表
1介绍了吸光度值记录组我,由4个牙齿与孔密封进行暂时的水泥,Coltosol F (COLTENE、Altstatten、瑞士)。