Department of Restorative Dentistry, Dental School of the Ludwig-Maximilians-University, Goethestr. 70, 80336, Munich, Germany.
Clin Oral Investig. 2013 Jan;17(1):251-7. doi: 10.1007/s00784-012-0707-3. Epub 2012 Mar 14.
Nanohybrid resin-based composites (RBCs) containing new types of matrix monomers such as dimer acid-based dimethacrylate or tricyclodecane-urethane are assumed to show decreased water uptake and therefore better resistance to hydrolytic degradation than RBCs using bisphenol A diglycidyl methacrylate (BisGMA) due to their hydropobic nature. Our study aimed to analyze the effect of aging on six nanohybrid RBCs, of which two are using these new types of monomers, with regard to differences in the mechanical properties of the materials.
Diametral tensile strength (DTS), Vickers hardness (HV), and creep were measured. Mechanical tests were performed after storing samples for 24 h in distilled water, as well as after aging (thermocycling for 5,000 cycles at 5-55°C and storage for 4 weeks either in distilled water, artificial saliva, or ethanol).
The effect of aging on all test parameters was lower than the effect of the material. This information was provided by a general linear model, showing higher partial η(2) values for the influence factor material than for the factor aging. The influence of aging on the micromechanical properties HV and creep was proven to be more sensitive than on the macromechanical property (DTS). This was also illustrated by lower η(2) values for the variable aging for DTS. An increase of the creep of all materials was observed after storage in alcohol.
The use of new types of monomers could not be shown to be a significant advantage to the other examined materials containing BisGMA.
Nanohybrid composites can be recommended as universal filling materials, whether based on new or conventional monomers.
纳米复合树脂基材料（RBC）中含有新型基质单体，如二聚酸二甲基丙烯酸酯或三环癸烷-聚氨酯，由于其疏水性，与使用双酚 A 二缩水甘油甲基丙烯酸酯（BisGMA）的 RBC 相比，假设其吸水率降低，因此对水解降解的抵抗力更好。本研究旨在分析两种新型单体的纳米复合 RBC 的老化对材料机械性能差异的影响。
测量了直径拉伸强度（DTS）、维氏硬度（HV）和蠕变。在将样品储存在蒸馏水中 24 小时后以及在老化（在 5-55°C 下热循环 5000 次并在蒸馏水中、人工唾液或乙醇中储存 4 周）后进行机械测试。
老化对所有测试参数的影响均低于材料的影响。这一信息由一般线性模型提供，显示出影响因素材料的部分η（2）值高于老化因素。老化对 HV 和蠕变等微观力学性能的影响比宏观力学性能（DTS）更敏感。这也说明了 DTS 变量老化的η（2）值较低。所有材料在储存于酒精后蠕变增加。
新型单体的使用不能被证明是其他含 BisGMA 的被检材料的显著优势。
纳米复合树脂可以作为通用填充材料推荐使用，无论其基于新型单体还是传统单体。
