In vitro aging behavior of dental composites considering the influence of filler content, storage media and incubation time

1. Objective: Over time dental composites age due to mechanical impacts such as chewing and chemical impacts such as saliva enzymes and food ingredients. For this research, the focus was placed on chemical degradation.The objective of this study was to simulate hydrolysis by using different food simulating liquids and to assess their impact on the mechanical parameter Vickers microhardness (MHV) and the physicochemical parameter contact angle (CA). 2. Methods: Specimen of three composites (d = 6 mm, h = 2 mm; n = 435) classified with respect to their filler content (wt%), namely low-filled, medium-filled and highly-filled, were stored for 0, 14, 30, 90 and 180 days in artificial saliva (pH 7), citric acid (pH 3; pH 5), lactic acid (pH 3; pH 5) and ethanol (40 %vol; 60 %vol) and assessed regarding to MHV and CA.Statistics: Kruskal-Wallis test, stepwise linear regression, bivariate Spearman Rank Correlation (p < 0.05). 3. Results: While stored in artificial saliva, acid and ethanol the...

1. 研究目的：牙科复合材料会随时间老化，其原因包括咀嚼等机械作用以及唾液酶、食物成分等化学作用。本研究聚焦于化学降解，旨在通过使用不同的食品模拟液模拟水解过程，并评估其对力学参数维氏显微硬度（Vickers microhardness, MHV）和理化参数接触角（contact angle, CA）的影响。 2. 研究方法：制备三种复合材料样本（直径d=6 mm，高度h=2 mm；样本量n=435），按填料含量（重量百分比，wt%）分为低填料、中填料和高填料三类。将样本分别在人工唾液（pH=7）、柠檬酸（pH=3；pH=5）、乳酸（pH=3；pH=5）及乙醇（体积分数40%；60%）中储存0、14、30、90和180天，并对其MHV和CA进行评估。统计方法：采用Kruskal-Wallis检验、逐步线性回归分析及双变量Spearman秩相关分析（p < 0.05）。 3. 研究结果：在人工唾液、酸类及乙醇中储存时，...