Salamoni Sinhori Bruna, de Andrada Mauro Amaral Caldeira, Carpena Lopes Guilherme, Monteiro Junior Sylvio, Baratieri Luiz Narciso
Federal University of Santa Catarina, Florianopolis, SC, Brazil.
Int J Biomater. 2017;2017:2078526. doi: 10.1155/2017/2078526. Epub 2017 Mar 23.
The polishing step of teeth preparations for crowns is a step often performed, so that there is an increased time during the clinical procedure. The aim of this study is to evaluate the marginal and internal adaptation of all-ceramic CAD/CAM lithium disilicate crowns in polished preparations for crown and nonpolished preparations for crowns. For this purpose, 20 first molars were selected, which were divided into two groups ( = 10) G1, teeth that received surface roughening similar to preparation without polishing, and G2 (control), polished preparations. After the preparations were completed the teeth were scanned (Cerec Bluecam, Sirona, Bensheim, Germany), and the crowns were designed and machined using CAD/CAM technology (Sirona, Bensheim, Germany). The adaptation of the pieces was evaluated using polyvinyl siloxane replicas and stereomicroscope photographs with 70x magnifications. The normality test indicated a nonnormal result, so a Man-Whitney nonparametric test was performed. One out of the 24 measured regions showed a statistically significant difference ( = 0.0494). With this study it can be concluded that crowns fabricated by CAD/CAM technology performed on unpolished preparations are not influenced by the internal marginal adaptation and the ceramic part and are different from polished preparations.
牙冠修复体预备的抛光步骤是临床操作中经常进行的一步，这使得临床操作时间增加。本研究的目的是评估全瓷CAD/CAM二硅酸锂冠在牙冠预备体抛光和未抛光情况下的边缘及内部适合性。为此，选择了20颗第一磨牙，分为两组（每组n = 10）：G1组，接受类似于未抛光预备体的表面粗糙化处理的牙齿；G2组（对照组），经过抛光处理的预备体。预备完成后，对牙齿进行扫描（德国本斯海姆西诺德公司的Cerec Bluecam），并使用CAD/CAM技术（德国本斯海姆西诺德公司）设计和制作牙冠。使用聚乙烯基硅氧烷复制件和放大70倍的体视显微镜照片评估修复体的适合性。正态性检验结果显示数据非正态分布，因此进行了曼-惠特尼非参数检验。在24个测量区域中，有1个区域显示出统计学上的显著差异（P = 0.0494）。通过本研究可以得出结论，在未抛光的预备体上用CAD/CAM技术制作的牙冠在内部边缘适合性和陶瓷部分不受影响，且与抛光的预备体不同。
