Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil.
Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil.
J Mech Behav Biomed Mater. 2023 May;141:105758. doi: 10.1016/j.jmbbm.2023.105758. Epub 2023 Mar 5.
This study investigated the effect of preheating an elastomeric urethane monomer (Exothane-24) experimental resin composite on its physicochemical properties. Two resin matrices were formulated: (a) 50 wt% Bisphenol-glycidyl methacrylate (Bis-GMA) and 50 wt% triethylene glycol dimethacrylate (TEGDMA); and (b) 20 wt% Exothane-24, 40 wt% Bis-GMA and 40 wt% TEGDMA. A photoinitiator system (0.25 wt% camphorquinone and 0.50 wt% ethyl-4-dimethylamino benzoate) and 65 wt% of the inorganic filler (20 wt% 0.05 μm silica and 80 wt% 0.7 μm BaBSiO glass) were added to both matrices. These formulations were then assigned to four groups: Exothane-24 (E); Exothane-24 plus preheating (EH); no Exothane-24 (NE); and no Exothane-24 plus preheating (NEH). NEH and EH were preheated at 69 °C. The dependent variables were as follows: film thickness (FT); polymerization shrinkage stress (PSS); gap width (GW); maximum rate of polymerization (Rp); and degree of conversion (DC). Data were statistically analyzed by two-way ANOVA and Tukey's test (α = 0.05). Preheating reduced FT for both composites. PSS and GW were significantly lower for EH, when compared with E. The DC for EH and NEH and the Rp for EH increased significantly. Preheating improved most of the physicochemical properties (FT, PSS, GW, and DC) of the experimental resin composite containing Exothane-24.
本研究探讨了预先加热弹性氨基甲酸乙酯单体（Exothane-24）实验性树脂复合材料对其物理化学性质的影响。配制了两种树脂基质：（a）50wt% 双酚 A 缩水甘油甲基丙烯酸酯（Bis-GMA）和 50wt% 三乙二醇二甲基丙烯酸酯（TEGDMA）；（b）20wt% Exothane-24、40wt% Bis-GMA 和 40wt% TEGDMA。加入光引发剂体系（0.25wt%樟脑醌和 0.50wt%乙基-4-二甲氨基苯甲酸酯）和 65wt%的无机填料（20wt%0.05μm 二氧化硅和 80wt%0.7μm BaBSiO 玻璃）。这些配方随后被分为四组：Exothane-24（E）；Exothane-24 加预热（EH）；无 Exothane-24（NE）；无 Exothane-24 加预热（NEH）。NEH 和 EH 在 69°C 下预热。依赖变量如下：薄膜厚度（FT）；聚合收缩应力（PSS）；间隙宽度（GW）；最大聚合速率（Rp）；和转化率（DC）。数据通过双因素方差分析和 Tukey 检验（α=0.05）进行统计分析。预热降低了两种复合材料的 FT。与 E 相比，EH 的 PSS 和 GW 明显较低。EH 和 NEH 的 DC 以及 EH 的 Rp 显著增加。预热提高了含有 Exothane-24 的实验性树脂复合材料的大部分物理化学性质（FT、PSS、GW 和 DC）。
