Beuer Florian, Naumann Michael, Gernet Wolfgang, Sorensen John A
Department of Prosthodontics, Ludwig-Maximilians University, Munich, Germany.
Clin Oral Investig. 2009 Sep;13(3):343-9. doi: 10.1007/s00784-008-0224-6. Epub 2008 Sep 4.
The purpose of this in vitro study was to compare the precision of fit of substructures milled from semi-sintered zirconia blocks fabricated with two different computer-assisted design (CAD)/computer-assisted manufacturing (CAM) systems. Three-unit posterior fixed dental prostheses (FDP) were fabricated for standardized dies (n = 10) with the Lava CAD/CAM system (Lava) and the Procera-bridge-zirconia CAD/CAM system (Procera). After cementation to the dies, the FDP were embedded and sectioned. Four cross-sections were made of each abutment tooth, and marginal and internal fit were evaluated under an optical microscope. A one-way analysis of variance was used to compare data (alpha = 0.05). Mean gap dimensions at the marginal opening for Lava and Procera were 15 (+/-7) microm and 9 (+/-5) microm, respectively. Mean marginal openings (P = 0.012) and internal adaptation at two out of three measurement locations were significantly different. Within the limitations of this study, the results suggest that the accuracy of both investigated systems is satisfactory for clinical use.
本体外研究的目的是比较用两种不同的计算机辅助设计（CAD）/计算机辅助制造（CAM）系统制作的半烧结氧化锆块体铣削而成的子结构的贴合精度。使用Lava CAD/CAM系统（Lava）和Procera-bridge-氧化锆CAD/CAM系统（Procera）为标准化模型（n = 10）制作三单位后牙固定义齿（FDP）。在将FDP粘结到模型上后，将其包埋并切片。每个基牙制作四个横截面，并在光学显微镜下评估边缘和内部贴合情况。采用单因素方差分析比较数据（α = 0.05）。Lava和Procera边缘开口处的平均间隙尺寸分别为15（±7）微米和9（±5）微米。在三个测量位置中的两个位置，平均边缘开口（P = 0.012）和内部适应性存在显著差异。在本研究的局限性内，结果表明，所研究的两种系统的精度对于临床应用来说是令人满意的。
