Department of Prosthodontics, Justus-Liebig University, Schlangenzahl 14, 35392 Giessen, Germany.
Dent Mater. 2021 Apr;37(4):e213-e230. doi: 10.1016/j.dental.2020.12.012. Epub 2021 Jan 30.
To assess energy dissipation capacities and surface damping abilities of different CAD/CAM restorative materials (CRMs) to characterize stress resistance during load peaks.
Using instrumented indentation testing (IIT), Martens hardness (HM) together with its elastic (η) and plastic index (η) and Leeb hardness (HLD) together with its deduced energy dissipation (HLD) were determined for eight ceramic, eight composite, and four polymer-based materials as well as three metals. The results were compared to those of bovine enamel. Ten indentations per material were performed at room temperature (23 ± 1 °C) on two separate specimens (12.0 × 12.0 × 3.5 mm) after water storage (24 h; 37.0 ± 1.0 °C). Hardness parameters were recorded, and data were analyzed with one-way MANOVA (Games-Howell post hoc tests, α = 0.05). Correlations between different parameters were tested (Pearson, α = 0.05).
Independently determined HLD, and η values substantiated different energy dissipation characteristics of CRM, whereby a strong correlation was observed for the two datasets (r = 0.956, p = 0.011). Ceramics had the significantly lowest values (p < 0.001) while both parameters revealed the highest surface damping effects for metals (p < 0.001), followed in both cases by bovine enamel. Energy dissipation of polymer and composite CRM was in between ceramics and bovine enamel (p < 0.001), whereas only for HLD did both show no significant difference (p > 0.05).
Promising new HLD and η data allow a reliable differentiation of energy dissipation and surface damping capacities of CRMs. Previously published rankings of edge chipping and loss tangent results were perfectly reproduced, especially by HLD.
评估不同 CAD/CAM 修复材料 (CRM) 的能量耗散能力和表面阻尼能力，以表征在峰值载荷下的抗应力能力。
使用仪器压痕测试 (IIT)，测定了 8 种陶瓷、8 种复合材料和 4 种聚合物基材料以及 3 种金属的马氏硬度 (HM) 及其弹性 (η) 和塑性指数 (η) 和里氏硬度 (HLD) 及其推断的能量耗散 (HLD)。将结果与牛牙釉质的结果进行比较。在室温（23±1°C）下，对两个单独的样本（12.0×12.0×3.5mm）进行了 10 次压痕测试，每次测试 10 个样本，每个样本在水储存（24h；37.0±1.0°C）后进行。记录硬度参数，并使用单向 MANOVA（Games-Howell 事后检验，α=0.05）对数据进行分析。测试了不同参数之间的相关性（Pearson，α=0.05）。
独立确定的 HLD 和 η 值证实了 CRM 的不同能量耗散特性，这两个数据集之间存在很强的相关性（r=0.956，p=0.011）。陶瓷的数值最低（p<0.001），而两个参数都显示出金属的最高表面阻尼效果（p<0.001），其次是牛牙釉质。聚合物和复合材料 CRM 的能量耗散处于陶瓷和牛牙釉质之间（p<0.001），而只有 HLD 两个参数之间没有显著差异（p>0.05）。
有前途的新 HLD 和 η 数据允许可靠地区分 CRM 的能量耗散和表面阻尼能力。以前发表的边缘崩裂和损耗角正切结果的排名得到了完美再现，尤其是通过 HLD。
