Department of Restorative Dentistry, School of Dentistry, University of Pernambuco, Camaragibe, Pernambuco, Brazil.
Acta Odontol Scand. 2013 Jan;71(1):215-22. doi: 10.3109/00016357.2012.654613. Epub 2012 Jan 30.
This study aimed to characterize the morphology of filler particles and to analyze the effect of shortened and extended photoactivation times on hardness (VHN) and cross-link density (CLD) of resin-based low-viscosity materials.
Sixteen commercially available materials were tested: four fissure sealants (Alpha Seal, Fluroshield Yellowed, Bioseal and Fluroshield White) and 12 flowable composites (Opallis T, Permaflo T, Opallis A2, Natural Flow A2, Master Flow A2, Permaflo A2, Filtek Z350 A2, Natural Flow O, Master Flow OA2, Opallis OA3.5, Filtek Z350 OA3, Opallis OP) at six curing times (10 s, 20 s, 30 s, 40 s, 50 s and 60 s). Specimens were fabricated (n = 5), analyzed by Scanning Electron Microscopy, by VHN and by CLD.
Unimodal and multimodal filler particles sizes with spherical and irregular shapes were observed. Unfilled materials were also detected. There were no differences among curing times for either VHN or CLD. Opallis A2 and Opallis OA3.5 showed the highest VHN at all curing times, whereas Master Flow A2 and Master Flow OA2 presented the lowest VHN. Opallis A2 presented the highest CLD at all curing times and Alpha Seal showed the lowest CLD.
Filler particle morphology differed among the resin-based low-viscosity materials tested. The shortest photoactivation time tested could yield similar VHN and CLD means to those provided by the most extended photoactivation time.
本研究旨在描述填料颗粒的形态，并分析缩短和延长光固化时间对树脂基低粘度材料硬度（VHN）和交联密度（CLD）的影响。
测试了 16 种市售材料：4 种窝沟封闭剂（Alpha Seal、Fluroshield Yellowed、Bioseal 和 Fluroshield White）和 12 种流动复合树脂（Opallis T、Permaflo T、Opallis A2、Natural Flow A2、Master Flow A2、Permaflo A2、Filtek Z350 A2、Natural Flow O、Master Flow OA2、Opallis OA3.5、Filtek Z350 OA3、Opallis OP），在 6 个固化时间（10s、20s、30s、40s、50s 和 60s）下进行测试。制备样本（n=5），通过扫描电子显微镜、VHN 和 CLD 进行分析。
观察到具有球形和不规则形状的单峰和多峰填料颗粒尺寸。还检测到未填充材料。VHN 和 CLD 均未因固化时间而异。在所有固化时间下，Opallis A2 和 Opallis OA3.5 的 VHN 最高，而 Master Flow A2 和 Master Flow OA2 的 VHN 最低。在所有固化时间下，Opallis A2 的 CLD 最高，而 Alpha Seal 的 CLD 最低。
测试的树脂基低粘度材料的填料颗粒形态不同。测试的最短光固化时间可以产生与最长光固化时间提供的相似的 VHN 和 CLD 平均值。
