R&D, In Vitro Research, Ivoclar Vivadent AG, Bendererstrasse 2, Schaan, Liechtenstein.
Dent Mater. 2010 Apr;26(4):306-19. doi: 10.1016/j.dental.2009.11.152. Epub 2009 Dec 29.
(1) To evaluate the changes in surface roughness and gloss after simulated toothbrushing of 9 composite materials and 2 ceramic materials in relation to brushing time and load in vitro; (2) to assess the relationship between surface gloss and surface roughness.
Eight flat specimens of composite materials (microfilled: Adoro, Filtek Supreme, Heliomolar; microhybrid: Four Seasons, Tetric EvoCeram; hybrid: Compoglass F, Targis, Tetric Ceram; macrohybrid: Grandio), two ceramic materials (IPS d.SIGN and IPS Empress polished) were fabricated according to the manufacturer's instructions and optimally polished with up to 4000 grit SiC. The specimens were subjected to a toothbrushing (TB) simulation device (Willytec) with rotating movements, toothpaste slurry and at three different loads (100g/250g/350g). At hourly intervals from 1h to 10h TB, mean surface roughness Ra was measured with an optical sensor and the surface gloss (Gl) with a glossmeter. Statistical analysis was performed for log-transformed Ra data applying two-way ANOVA to evaluate the interaction between load and material and load and brushing time.
There was a significant interaction between material and load as well as between load and brushing time (p<0.0001). The microhybrid and hybrid materials demonstrated more surface deterioration with higher loads, whereas with the microfilled resins Heliomolar and Adoro it was vice versa. For ceramic materials, no or little deterioration was observed over time and independent of the load. The ceramic materials and 3 of the composite materials (roughness) showed no further deterioration after 5h of toothbrushing. Mean surface gloss was the parameter which discriminated best between the materials, followed by mean surface roughness Ra. There was a strong correlation between surface gloss and surface roughness for all the materials except the ceramics. The evaluation of the deterioration curves of individual specimens revealed a more or less synchronous course suspecting hinting specific external conditions and not showing the true variability in relation to the tested material.
The surface roughness and gloss of dental materials changes with brushing time and load and thus results in different material rankings. Apart from Grandio, the hybrid composite resins were more prone to surface changes than microfilled composites. The deterioration potential of a composite material can be quickly assessed by measuring surface gloss. For this purpose, a brushing time of 10h (=72,000 strokes) is needed. In further comparative studies, specimens of different materials should be tested in one series to estimate the true variability.
（1）评估 9 种复合材料和 2 种陶瓷材料在体外模拟刷牙后，表面粗糙度和光泽度随刷牙时间和负荷的变化；（2）评估表面光泽度与表面粗糙度之间的关系。
根据制造商的说明制作 8 个复合材料（微填充：Adoro、Filtek Supreme、Heliomolar；微混合：Four Seasons、Tetric EvoCeram；混合：Compoglass F、Targis、Tetric Ceram；大混合：Grandio）和 2 种陶瓷材料（IPS d.SIGN 和 IPS Empress 抛光）的平板试件，并使用最高可达 4000 粒度 SiC 的砂纸进行最佳抛光。将试件放入旋转运动、牙膏浆和三种不同载荷（100g/250g/350g）的 Willytec 牙刷模拟装置中。从 1h 到 10hTB 每隔 1h 测量一次光学传感器的平均表面粗糙度 Ra 和光泽度计的表面光泽度（Gl）。对 Ra 数据进行对数转换后，采用双向方差分析评估载荷与材料和载荷与刷牙时间之间的相互作用。
材料与载荷以及载荷与刷牙时间之间存在显著的相互作用（p<0.0001）。微混合和混合材料在较高载荷下表现出更多的表面劣化，而 Heliomolar 和 Adoro 微填充树脂则相反。对于陶瓷材料，随着时间的推移，无论载荷如何，都没有或很少观察到劣化。陶瓷材料和 3 种复合材料（粗糙度）在刷牙 5h 后没有进一步的劣化。平均表面光泽度是区分材料的最佳参数，其次是平均表面粗糙度 Ra。除了陶瓷材料外，所有材料的表面光泽度和表面粗糙度之间都存在很强的相关性。对个别试件的劣化曲线的评估表明，在不同的材料之间存在着或多或少同步的过程，这表明存在特定的外部条件，而不是表现出与所测试材料真正的可变性。
随着刷牙时间和负荷的增加，牙科材料的表面粗糙度和光泽度会发生变化，从而导致不同的材料排名。除了 Grandio 之外，混合复合材料比微填充复合材料更容易发生表面变化。通过测量表面光泽度，可以快速评估复合材料的劣化潜力。为此，需要进行 10h（=72,000 次）的刷牙。在进一步的比较研究中，应在同一系列中测试不同材料的试件，以估计真实的可变性。
