Department of Restorative Dentistry and Buccofacial Prostheses, Faculty of Dentistry, Complutense University of Madrid, Plaza Ramón y Cajal, S/N, Ciudad Universitaria, 28040, Madrid, Spain.
Clin Oral Investig. 2019 Apr;23(4):1745-1751. doi: 10.1007/s00784-018-2606-8. Epub 2018 Aug 30.
To compare clinical aspects of all-ceramic crowns fabricated from conventional and digital impressions.
Thirty patients with 30 posterior teeth with the need of a crown restoration were selected. Zirconia-based ceramic crowns were made using an intraoral digital impression system (TRIOS®, 3shape) and two-step silicone impression technique. Two external blinded operators evaluated the all-ceramic crowns. Five selection items were assessed of which four were clinical: "marginal fit," "occlusal contacts," "interproximal contact points," and "primary retention." Then, the last selection item "final selection" was assessed when the operators considering all the variables had to select which of the digital or conventional crown had the best clinical conditions. Data was analyzed using Kappa index test and the Pearson's chi-square test (α = 0.05).
For the items marginal fit and interproximal contact points, moderate agreement between the two operators was described and significant differences were found between the two study groups. Conversely, for the variables primary retention and occlusal contacts, the agreement between the operators was fair and no significant differences were found. For the final selection, a substantial agreement was reached between the two operators and significant differences were found between the two groups (p < 0.05).
In most cases and in a significant way, the digital crowns had better clinical conditions according to both evaluators. The digital crowns were statistically superior for the interproximal contact points and marginal fit. For the variables occlusal contacts and primary retention, no difference between the two groups was observed.
Digital intraoral impressions can be used for manufacturing ceramic crowns, with the same or better clinical results as conventional impressions.
比较传统印模和数字印模制作全瓷冠的临床效果。
选择 30 名需要进行后牙牙冠修复的患者，使用口内数字印模系统（TRIOS®，3shape）和两步硅橡胶印模技术制作氧化锆基陶瓷冠。两名外部盲审操作人员对全瓷冠进行评估。评估了 5 个选择项目，其中 4 个为临床项目：“边缘适合性”、“咬合接触”、“邻面接触点”和“固位力”。然后，当操作人员考虑所有变量时，必须选择数字印模或传统印模制作的牙冠具有更好的临床条件，评估最后一个选择项目“最终选择”。使用 Kappa 指数检验和 Pearson 卡方检验（α=0.05）进行数据分析。
在两名操作人员之间，对于边缘适合性和邻面接触点这两个项目，描述了中度一致性，并且在两个研究组之间发现了显著差异。相反，对于固位力和咬合接触这两个变量，操作人员之间的一致性为中等，并且在两个组之间未发现显著差异。对于最终选择，两名操作人员之间达成了实质性的一致，并且在两个组之间发现了显著差异（p＜0.05）。
在大多数情况下，并且具有显著意义，数字冠根据两名评估者具有更好的临床效果。在邻面接触点和边缘适合性方面，数字冠具有统计学优势。对于咬合接触和固位力这两个变量，两组之间未观察到差异。
数字口内印模可用于制作陶瓷冠，具有与传统印模相同或更好的临床效果。
