Hokkaido University, Faculty of Dental Medicine, Department of Biomaterials and Bioengineering, Kita 13, Nishi 7, Sapporo, Hokkaido, Japan; Sun Medical Co., Ltd., 571-2 Furutaka-cho, Moriyama, Shiga 524-0044, Japan.
National Institute of Advanced Industrial Science and Technology (AIST), Health Research Institute, 2217-14 Hayashi-cho, Takamatsu 761-0395, Japan; Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Department of Pathology & Experimental Medicine, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
Dent Mater. 2021 Jun;37(6):e391-e398. doi: 10.1016/j.dental.2021.02.023. Epub 2021 Mar 20.
Bisphenol A-glycidyl methacrylate (Bis-GMA) and urethane dimethacrylate (UDMA) are widely used as the primary components of (meth)acrylic monomers. However, the use of Bis-GMA, which is a bisphenol A derivative, in dentistry is being questioned after bisphenol A was found to exhibit estrogenic activity. Although UDMA is being considered as a substitute for bis-GMA, the mechanical properties of cured resin composites containing UDMA are less than desirable. Therefore, in this study, we developed new alternative (meth)acrylic monomers to enhance the mechanical strength of cured composite resins.
Five urethane acrylic monomers were synthesized in this study as (meth)acrylic monomer substituents to replace Bis-GMA and UDMA. The elastic modulus, strength, and breaking energy values of cured resins consisting of mixtures of the urethane acrylates and diluting monomers were determined using the three-point flexural test. The data obtained were analyzed using one-way ANOVA and the post-hoc Tukey HSD tests (p < 0.05). Viscosities of the urethane acrylic monomers were measured with a cone-plate viscometer. Refractive indices of the urethane acrylic monomers were determined with an Abbe refractometer.
The results of the three-point flexural tests revealed that the cured urethane acrylic monomer-based resin exhibited higher elastic modulus (up to 40%) and strength (up to 21%) compared to the cured UDMA-based resin. Viscosity and refractive index of the urethane acrylic monomers were between those of UDMA and Bis-GMA.
The developed urethane diacrylates prepared from diisocyanates which have an aromatic or aliphatic ring, 1,3-bis(1-isocyanato-1-methylethyl)benzene (TMXDI), 1,3-bis(isocyanatomethyl)benzene (XDI), or norbornane diisocyanate (NBDI) are worth considering as alternative options of Bis-GMA and UDMA for restorative resin composites.
双酚 A-缩水甘油甲基丙烯酸酯（Bis-GMA）和 尿烷二甲基丙烯酸酯（UDMA）被广泛用作（甲基）丙烯酸单体的主要成分。然而，在发现双酚 A 具有雌激素活性后，双酚 A 的衍生物 Bis-GMA 在牙科中的使用受到质疑。虽然 UDMA 被认为是 Bis-GMA 的替代品，但含有 UDMA 的固化树脂复合材料的机械性能不尽如人意。因此，在本研究中，我们开发了新的替代（甲基）丙烯酸单体，以提高固化复合树脂的机械强度。
本研究合成了五种尿烷丙烯酸单体作为（甲基）丙烯酸单体取代物，以替代 Bis-GMA 和 UDMA。通过三点弯曲试验确定由尿烷丙烯酸酯和稀释单体混合物组成的固化树脂的弹性模量、强度和断裂能值。使用单向方差分析和事后 Tukey HSD 检验（p<0.05）对获得的数据进行分析。使用锥板粘度计测量尿烷丙烯酸单体的粘度。使用阿贝折射仪测定尿烷丙烯酸单体的折射率。
三点弯曲试验结果表明，与固化的 UDMA 基树脂相比，基于固化的尿烷丙烯酸单体的树脂表现出更高的弹性模量（高达 40%）和强度（高达 21%）。尿烷丙烯酸单体的粘度和折射率在 UDMA 和 Bis-GMA 之间。
由具有芳环或脂环的二异氰酸酯、1,3-双（1-异氰酸根-1-甲基乙基）苯（TMXDI）、1,3-双（异氰酸根甲基）苯（XDI）或降冰片烷二异氰酸酯（NBDI）制备的开发的尿烷二丙烯酸酯可用作修复树脂复合材料中 Bis-GMA 和 UDMA 的替代选择。
