Department of Restorative Dentistry, Faculty of Dentistry, Ordu University, Ordu, Turkey.
Department of Pediatric Dentistry, Faculty of Dentistry, Ordu University, Ordu, Turkey.
Niger J Clin Pract. 2021 Oct;24(10):1442-1449. doi: 10.4103/njcp.njcp_676_20.
Residual monomers released from composite resins have cytotoxic, mutagenic, and estrogenic effects. Mode of polymerization and application thickness are important for monomer release.
The aim of this study was to investigate the effects of different modes of a third-generation light-curing unit (LCU) and layer thickness on residual monomer released from two different bulk-fill composite resins. A total of 80 samples were prepared for each bulk-fill composite using a mold. Each bulk-fill composite was divided into four groups according to polymerization mode (standard and extra power) and layer thickness (2 and 4 mm). In addition, four groups were divided into four subgroups according to time periods (1 h, 24 h, 3 days, and 7 days).
The samples were polymerized with VALO LED device. The amount of residual monomer was measured with High-Performance Liquid Chromatography (HPLC). All statistical analyses were processed using SPSS Version 23.0. The normal distribution of data was confirmed using Kolmogorov-Smirnov Normal Distribution Test and Shapiro-Wilk Normal Distribution Test. When the distribution was normal, parametric tests, Student's t test and one-way ANOVA, were used. When the distribution was not normal, non-parametric tests, Mann-Whitney U test, and Kruskal-Wallis testwere used.
It was found that the standard mode of LCU produced lower amounts of TEGDMA, Bis-GMA, and UDMA in both composite materials. In addition, when the layer thickness increased, TEGDMA, Bis-GMA, and UDMA releases increased, too.
This study revealed that the amount of residual monomers released from bulk-fill composites was affected by layer thickness and polymerization time.
复合树脂中释放的残留单体具有细胞毒性、致突变性和雌激素作用。聚合方式和应用厚度对单体释放很重要。
本研究旨在研究第三代光固化器（LCU）的不同模式和层厚对两种不同块状填充型复合树脂中残留单体释放的影响。使用模具为每种块状填充型复合树脂制备了 80 个样本。根据聚合模式（标准和超强）和层厚（2 和 4 毫米），将每种块状填充型复合材料分为四组。此外，根据时间段（1 小时、24 小时、3 天和 7 天）将四组分为四个亚组。
使用 VALO LED 设备聚合样本。使用高效液相色谱法（HPLC）测量残留单体的量。所有统计分析均使用 SPSS 版本 23.0 进行处理。使用 Kolmogorov-Smirnov 正态分布检验和 Shapiro-Wilk 正态分布检验确认数据的正态分布。当分布正常时，使用参数检验、Student's t 检验和单因素方差分析。当分布不正常时，使用非参数检验、Mann-Whitney U 检验和 Kruskal-Wallis 检验。
发现 LCU 的标准模式在两种复合材料中产生的 TEGDMA、Bis-GMA 和 UDMA 量较低。此外，当层厚增加时，TEGDMA、Bis-GMA 和 UDMA 的释放量也增加。
本研究表明，块状填充型复合材料中残留单体的释放量受层厚和聚合时间的影响。
