Study on Durability of Dental Adhesive Materials

牙科粘合材料的耐久性研究

• 批准号: 63045008
• 负责人: MIYAIRI Hiroo
• 金额: $ 3.84万
• 依托单位: Tokyo Medical and Dental University (1989-1990)Mining College, Akita University (1988)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63045008/
• 关键词: Dental Adhesive Materials; Composite Resins; Resin Cements; Strength of Adhesives; Wear; Thailand; Geothermal resources; Heat source; Reservoir engineering; Age dating; Isotope geochemistry; 土壌ガス

We study here the durability of dental adhesive materials. The evaluation of durability is so important that it includes not only the degradation of adhesive strength but also the marginal leakage, degradation of materials themselves and the wear properties.1. Dental composite resins are the most popular dental adhesive materials. The wear properties are one of the most serious concerns of many clinicians. The mechanism of wear phenomena includes the wear of the matrix resins themseleves and the falling off of fillers after the degradation of matrix-filler interfaces. In coming decades, the improvement of these materials will be focused on the strengthening of the matrix-filler interfaces because the strengthening of resins the organic materials being seemed so difficult. Thus we investigate the degradation of matrix-filler interfaces here. First we improve the wear testing machine which simulates the wear mechanism in the oral environment, by the applications of elastomer materials be … More tween the experimental resin specimens and opposite steel cylinders. It was verified that the wears similar to those in oral environment can be realized by this machine.2. In order to improve the in vitro simulation of the degradation mechanism in the oral environment, we further attempt the repeated application of mechanical stresses to the resin specimens, prior to the wear testings. The materials choosed are the micro-filler type and those for resin-inlay. Then we found that so high stresses as one third of ultimates strength and so many times as 1,000,000 do not induce significant degradation of wear properties. The SEM observation also reveal no significant differences on the wear surfaces. It is concluded that recent commercial materials as tested are so improved that no significant degradation will be observed after the dry fatigue testings. The degradation may be accelerated by the wet fatigue testings.3. The durability of adhesive strength is the most important concerns for adhesive resin cement. Hence next we develop the load application apparatus for the adhesive specimens held in water. The influence of mechanical stresses and environmental effects are examined for the composite resin type resin cements. Then it is found that the simultaneous applications of the mechanical and environmental effect is essential to the acceleration of the adhesive strength degradation. The sole application of mechanical stresses without aqueous environment or the holding of specimens in aqueous environment without mechanical stresses do not induce significant degradation in specimens. Further, the tensile stresses are found to be more effective than the shear stresses for the acceleration of the degradation.4. Marginal leakages also are important problems for dental resin cements. So we try to install the specimens for monitoring crack extensions to the above mentioned load application apparatus. We examined the two distinct types of adhesives and compare the results, the one is composite resin type whereas the other do not contain any fillers. The slow crack extension was observed in the soft adhesives. On the other hand, brittle fracture is observed in rigid adhesives. Less

我们在这里研究牙科粘合材料的耐久性。耐久性的评价非常重要，它不仅包括粘合强度的退化，还包括边缘渗漏、材料本身的退化和磨损性能。 1．牙科复合树脂是最流行的牙科粘合材料。磨损性能是许多临床医生最关心的问题之一。磨损现象的机理包括基体树脂本身的磨损和基体-填料界面降解后填料的脱落。未来几十年，这些材料的改进将集中在基质-填料界面的强化上，因为树脂和有机材料的强化似乎非常困难。因此，我们在这里研究基质-填料界面的退化。首先，我们改进了模拟口腔环境中磨损机制的磨损试验机，通过在实验树脂样本和相对的钢柱之间应用弹性体材料。经验证，该机可以实现与口腔环境类似的佩戴效果。 2．为了改进口腔环境中降解机制的体外模拟，我们进一步尝试在磨损测试之前对树脂样本重复施加机械应力。所选择的材料是微填料型和树脂镶嵌型。然后我们发现，高达极限强度三分之一和 1,000,000 倍的高应力不会导致磨损性能显着下降。 SEM 观察也显示磨损表面没有显着差异。结论是，最近测试的商业材料得到了很大的改进，以至于在干疲劳测试后不会观察到明显的退化。湿疲劳试验可能会加速降解。3．粘合强度的耐久性是粘合树脂水泥最重要的考虑因素。因此，接下来我们开发了用于水中粘合样本的负载施加装置。研究了复合树脂型树脂水泥的机械​​应力和环境效应的影响。然后发现机械和环境效应的同时施加对于粘合强度退化的加速至关重要。在没有水环境的情况下单独施加机械应力或者在没有机械应力的水环境中保持样品不会引起样品的显着降解。此外，发现拉应力比剪切应力更能有效加速降解。4．边缘渗漏也是牙科树脂粘固剂的重要问题。因此，我们尝试将用于监测裂纹扩展的样本安装到上述载荷施加装置上。我们检查了两种不同类型的粘合剂并比较了结果，一种是复合树脂型，而另一种则不含任何填料。在软粘合剂中观察到缓慢的裂纹扩展。另一方面，在硬质粘合剂中观察到脆性断裂。较少的

项目成果

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高岛，I.：地热资源委员会，交易。