Department of Prosthodontics, Dental Material Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
J Prosthodont. 2011 Apr;20(3):190-4. doi: 10.1111/j.1532-849X.2011.00694.x. Epub 2011 Apr 4.
Long-term success of metal ceramic restorations depends on metal ceramic bond strength. The purpose of this study was to determine whether recasting of base-metal alloys has any effect on metal ceramic bond strength.
Super Cast and Verabond base-metal alloys were used to cast 260 wax patterns. The alloy specimens were equally divided into five groups and cast as: group A 0.0%, B 25%, C 50%, D 75%, and E 100% once-cast alloy. Each group was divided into two subgroups: the first group was cast with Super Cast and the second with Verabond. In each subgroup half of the cast alloys were veneered with Vita VMK 68 and the others with Ceramco 3.
Recasting decreased bond strength (p < 0.006) when used for 50% once-cast alloy. Group E with 100% new Super Cast alloy veneered with Vita VMK 68 porcelain had the highest bond strength (30.75 ± 9.58 MPa), and group B including 25% new and 75% recast Super Cast alloy veneered with the same porcelain had the lowest bond strength (21.72 ± 5.19 MPa).
By adding over 50% once-cast alloy in base-metal alloys, metal-ceramic bond strength decreases significantly.
金属陶瓷修复体的长期成功取决于金属陶瓷结合强度。本研究旨在确定重熔贱金属合金是否会影响金属陶瓷结合强度。
使用 Super Cast 和 Verabond 贱金属合金铸造 260 个蜡型。将合金试件等分为五组，分别铸造为：A 组 0.0%、B 组 25%、C 组 50%、D 组 75%和 E 组 100%一次铸造合金。每组分为两组：第一组用 Super Cast 铸造，第二组用 Verabond 铸造。在每个亚组中，一半的铸造合金用 Vita VMK68 贴面，另一半用 Ceramco3 贴面。
重熔会降低结合强度（p < 0.006），当用于 50%一次铸造合金时。用 100%新 Super Cast 合金和 Vita VMK68 烤瓷贴面的 E 组具有最高的结合强度（30.75 ± 9.58 MPa），而包括 25%新合金和 75%重熔 Super Cast 合金并用相同烤瓷贴面的 B 组具有最低的结合强度（21.72 ± 5.19 MPa）。
在贱金属合金中添加超过 50%的一次铸造合金会显著降低金属陶瓷结合强度。
