Senior Teaching and Research Assistant, Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
Senior Teaching and Research Assistant, Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
J Prosthet Dent. 2019 Feb;121(2):252-257. doi: 10.1016/j.prosdent.2018.04.020. Epub 2018 Jul 20.
Clinical trials are needed to evaluate the digital and conventional fabrication technology for providing fixed partial dentures (FPDs).
The purpose of the second part of this clinical study was to compare the laboratory production time for tooth-supported, 3-unit FPDs by means of computer-aided design and computer-aided manufacturing (CAD-CAM) systems and a conventional workflow. In addition, the quality of the 3-unit framework of each treatment group was evaluated clinically.
For each of 10 participants, a 3-unit FPD was fabricated. Zirconia was used as the framework material in the CAD-CAM systems and included Lava C.O.S. CAD software (3M) and centralized CAM (group L); CARES CAD software (Institut Straumann AG) and centralized CAM (group iT); and CEREC Connect CAD software (Dentsply Sirona) and centralized CAM (group C). The noble metal framework in the conventional workflow (group K) was fabricated by means of the traditional lost-wax technique. All frameworks were evaluated clinically before veneering. The time for the fabrication of the cast, the 3-unit framework, and the veneering process was recorded. In addition, chairside time during the clinical appointment for the evaluation of the framework was recorded. The paired Wilcoxon test together with appropriate Bonferroni correction was applied to detect differences among treatment groups (α=.05).
The total effective working time (mean ±standard deviation) for the dental technician was 220 ±29 minutes in group L, 217 ±23 minutes in group iT, 262 ±22 minutes in group C, and 370 ±34 minutes in group K. The dental technician spent significantly more time in the conventional workflow than in the digital workflow, independent of the CAD-CAM systems used (P<.001).
Irrespective of the CAD-CAM system, the overall laboratory time for the dental technician was significantly less for a digital workflow than for the conventional workflow.
需要进行临床试验来评估数字化和传统制作技术在提供固定局部义齿（FPD）方面的效果。
本临床研究第二部分的目的是比较计算机辅助设计和计算机辅助制造（CAD-CAM）系统与传统工作流程在制作牙支持式三单位 FPD 时的实验室生产时间。此外，还评估了每个治疗组的三单位框架的临床质量。
为每位参与者制作一个三单位 FPD。氧化锆被用作 CAD-CAM 系统中的框架材料，包括 Lava C.O.S. CAD 软件（3M）和集中式 CAM（组 L）；CARES CAD 软件（Institut Straumann AG）和集中式 CAM（组 iT）；以及 CEREC Connect CAD 软件（登士柏西诺德）和集中式 CAM（组 C）。传统工作流程中的贵金属框架（组 K）通过传统失蜡技术制作。所有框架在贴面前均进行临床评估。记录铸造、三单位框架和贴面过程的制作时间。此外，还记录了临床就诊期间评估框架时的椅旁时间。采用配对 Wilcoxon 检验和适当的 Bonferroni 校正来检测治疗组之间的差异（α=.05）。
组 L 的牙科技术员总有效工作时间（平均值±标准差）为 220±29 分钟，组 iT 为 217±23 分钟，组 C 为 262±22 分钟，组 K 为 370±34 分钟。无论使用何种 CAD-CAM 系统，牙科技术员在传统工作流程中花费的时间明显多于数字化工作流程（P<.001）。
无论 CAD-CAM 系统如何，数字化工作流程的整体实验室时间对于牙科技术员来说明显短于传统工作流程。
