Beun Sébastien, Bailly Christian, Devaux Jacques, Leloup Gaëtane
School of Dentistry and Stomatology, Université catholique de Louvain, Brussels, Belgium.
Dent Mater. 2008 Apr;24(4):548-55. doi: 10.1016/j.dental.2007.05.019. Epub 2007 Jul 30.
The purpose of this research was to determine the viscoelastic properties of commercially available flowable resin composites and resin-based pit and fissure sealants. The weight percentage of filler particles and the morphology of the filler particles were also investigated.
Eight flowable resin composites (Admira Flow, Filtek Flow, FlowLine, Grandio Flow, Point-4 Flowable, Revolution Formula 2, Tetric Flow and X-Flow) and four pit and fissure sealants (Clinpro, Delton FS+, Estiseal F and Guardian Seal) were tested. Rheological measurements were performed using a dynamic oscillation rheometer. The filler weight content was determined by thermogravimetric analysis (TGA) and the morphology of the particles was investigated by scanning-electron microscopy (SEM).
Flowable resin composites are non-Newtonian, shear-thinning materials. As the shear rate increased, the complex viscosity decreased drastically. They all showed elasticity even at the lowest frequencies. They also all showed thixotropy. Pit and fissure sealants are non-Newtonian, very low-viscosity fluids. No correlation was found between the rheological properties and the filler weight content or the particles' shape.
Huge differences are observed in the viscosity and flow characteristics of flowable resin composites that can have a potential influence on their clinical behavior during handling and thus on their clinical indications. Pit and fissure sealants show very different rheological properties from one another.
本研究旨在测定市售可流动树脂复合材料和树脂基窝沟封闭剂的粘弹性特性。同时还研究了填料颗粒的重量百分比和填料颗粒的形态。
测试了八种可流动树脂复合材料（Admira Flow、Filtek Flow、FlowLine、Grandio Flow、Point-4 Flowable、Revolution Formula 2、Tetric Flow和X-Flow）和四种窝沟封闭剂（Clinpro、Delton FS+、Estiseal F和Guardian Seal）。使用动态振荡流变仪进行流变学测量。通过热重分析（TGA）确定填料重量含量，并通过扫描电子显微镜（SEM）研究颗粒的形态。
可流动树脂复合材料是非牛顿剪切变稀材料。随着剪切速率的增加，复数粘度急剧下降。即使在最低频率下，它们都表现出弹性。它们还都表现出触变性。窝沟封闭剂是非牛顿超低粘度流体。在流变学性质与填料重量含量或颗粒形状之间未发现相关性。
可流动树脂复合材料在粘度和流动特性方面存在巨大差异，这可能会对其在操作过程中的临床行为产生潜在影响，进而影响其临床适应症。窝沟封闭剂彼此之间表现出非常不同的流变学性质。
