Department of Pediatric Dentistry, Alborz university of Medical Sciences, Karaj, Iran.
Student Research Committee, Alborz University of Medical Sciences, Karaj, Iran.
Clin Exp Dent Res. 2022 Dec;8(6):1605-1613. doi: 10.1002/cre2.656. Epub 2022 Sep 5.
Since composites still face a critical problem called polymerization shrinkage and bulk-fill composites have reported acceptable results for this issue, this study aims to assess the polymerization shrinkage of a new bulk-fill flowable composite (G-aenial bulk injectable [GBI]) and compare it to other bulk-fill and conventional composites.
In this in vitro study, 25 composite discs were fabricated using three bulk-fill and two conventional composites. They were bonded to a microscopic slide and were covered by a coverslip. This assembly was transferred to a linear variable differential transformer and composite samples were cured from underneath the slides. Dimensional changes formed in composite samples were recorded. Data were analyzed using analysis of variance followed by post hoc Tukey's and Dunnett's tests.
The groups were significantly different regarding polymerization shrinkage. G-aenial bulk injectable and G-aenial universal flo showed significantly higher polymerization shrinkage than other composites at 30, 60, and 1800 s after light irradiation, while X-tra fil and Filtek Z250 showed the lowest polymerization shrinkage at the aforementioned time points.
According to the results, the new composite had polymerization shrinkage similar to the conventional one. Bulk-fill composites reported similar or lower shrinkage to conventional composites.
由于复合材料仍面临聚合收缩这一关键问题，而大量填充型复合材料在该问题上的报告结果可接受，本研究旨在评估一种新型大量填充型可流动复合材料（G-aenial bulk injectable [GBI]）的聚合收缩情况，并将其与其他大量填充型和传统复合材料进行比较。
在这项体外研究中，使用三种大量填充型和两种传统复合材料制备了 25 个复合盘。将它们粘接到显微镜载玻片上，并盖上盖玻片。将该组件转移到线性可变差动变压器上，从载玻片下方对复合样品进行固化。记录复合样品中形成的尺寸变化。使用方差分析对数据进行分析，然后使用事后 Tukey 和 Dunnett 检验进行比较。
各组在聚合收缩方面存在显著差异。在光照后 30、60 和 1800 秒时，G-aenial bulk injectable 和 G-aenial universal flo 的聚合收缩率明显高于其他复合材料，而 X-tra fil 和 Filtek Z250 在上述时间点的聚合收缩率最低。
根据结果，新型复合材料的聚合收缩与传统复合材料相似。大量填充型复合材料的收缩率与传统复合材料相似或更低。
