Kanat-Ertürk Burcu, Saridağ Serkan, Köseler Ege, Helvacioğlu-Yiğit Dilek, Avcu Egemen, Yildiran-Avcu Yasemin
Department of Prosthodontics, Kocaeli University, Faculty of Dentistry.
Department of Endodontics, Kocaeli University, Faculty of Dentistry.
Dent Mater J. 2018 Mar 30;37(2):256-265. doi: 10.4012/dmj.2017-035. Epub 2017 Dec 29.
The objectives of this study were to compare the fracture strength of endocrown restorations fabricated with different preparation depth and various CAD/CAM ceramics, and to assess the fracture types. Endodontically treated 100 extracted human permanent maxillary centrals were divided into two preparation depth groups as short (S: 3-mm-deep) and long (L: 6-mm-deep), then five ceramic subgroups, namely: feldspathic-ceramic (Vita Mark II-VM2), lithium-disilicate glass-ceramic (IPS e.max CAD-E.max), resin-ceramic (LAVA Ultimate-LU), polymer infiltrated ceramic (Vita Enamic-VE) and monoblock zirconia (inCoris TZI-TZI) (n=10/subgroup). The endocrowns were fabricated by CAD/CAM and were cemented with resin cement (RelyX U200). The teeth were thermally cycled (5,000cycles) and fracture tests were performed at 45º angle to the teeth. The data were statistically analyzed (Kruskal-Wallis, Mann Whitney U), failure modes were evaluated with stereomicroscopy. Zirconia group provided the statistically highest fracture strength, but also exhibited non-repairable failures. Preparation depth has an effect on the fracture strength only for feldspathic ceramic.
本研究的目的是比较用不同预备深度和各种CAD/CAM陶瓷制作的内冠修复体的断裂强度，并评估断裂类型。选取100颗经过根管治疗的拔除人类上颌中切牙，分为两个预备深度组，即短深度组（S：3mm深）和长深度组（L：6mm深），然后再分为五个陶瓷亚组，分别为：长石质陶瓷（维他美克II-VM2）、二硅酸锂玻璃陶瓷（义获嘉e.max CAD-E.max）、树脂陶瓷（LAVA Ultimate-LU）、聚合物渗透陶瓷（维他易美-VE）和一体式氧化锆（inCoris TZI-TZI）（每组n = 10）。内冠通过CAD/CAM制作，并用树脂水门汀（RelyX U200）粘结。对牙齿进行热循环（5000次循环），并以与牙齿成45°角的方向进行断裂试验。对数据进行统计学分析（Kruskal-Wallis检验、Mann Whitney U检验），用体视显微镜评估失效模式。氧化锆组的断裂强度在统计学上最高，但也表现出不可修复的失效情况。预备深度仅对长石质陶瓷的断裂强度有影响。
