Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
Clin Oral Implants Res. 2021 Oct;32 Suppl 21(Suppl 21):289-302. doi: 10.1111/clr.13801.
To systematically review the dental literature for clinical studies reporting on production time, effectiveness and/or costs of additive and subtractive computer-aided manufacturing (CAM) of implant prostheses.
A systematic electronic search for clinical studies from 1990 until June 2020 was performed using the online databases Medline, Embase and Cochrane. Time required for the computer-aided design (CAD) process, the CAM process, and the delivery of the CAD-CAM prostheses were extracted. In addition, articles reporting on the effectiveness and the costs of both manufacturing technologies were included.
Nine clinical studies were included reporting on subtractive CAM (s-CAM; 8 studies) and additive CAM (a-CAM; 1 study). Eight studies reported on the s-CAM of prosthetic and auxiliary components for single implant crowns. One study applied a-CAM for the fabrication of an implant bar prototype. Time was provided for the CAD process of implant models (range 4.9-11.8 min), abutments (range 19.7-32.7 min) and crowns (range 11.1-37.6 min). The time for s-CAM of single implant crown components (abutment/crown) ranged between 8.2 and 25 min. Post-processing (e.g. sintering) was a time-consuming process (up to 530 min). At delivery, monolithic/veneered CAD-CAM implant crowns resulted in additional adjustments chairside (51%/93%) or labside (11%/19%).
No scientific evidence exists on production time, effectiveness and costs of digital workflows comparing s-CAM and a-CAM. For both technologies, post-processing may substantially contribute to the production time. Considering effectiveness, monolithic CAD-CAM implant crowns may be preferred compared to veneered CAD-CAM crowns.
系统综述牙科文献中关于报告种植体修复体增材和减材计算机辅助制造（CAM）的生产时间、效果和/或成本的临床研究。
从 1990 年至 2020 年 6 月，使用在线数据库 Medline、Embase 和 Cochrane 对临床研究进行了系统的电子检索。提取计算机辅助设计（CAD）过程、CAM 过程和 CAD-CAM 修复体交付所需的时间。此外，还包括报告两种制造技术的效果和成本的文章。
纳入了 9 项临床研究，分别报告了减材 CAM（s-CAM；8 项研究）和增材 CAM（a-CAM；1 项研究）。8 项研究报告了用于单牙种植体冠修复体和辅助部件的 s-CAM。一项研究应用 a-CAM 制造种植体杆原型。提供了用于植入物模型的 CAD 处理时间（范围 4.9-11.8 分钟）、基台（范围 19.7-32.7 分钟）和冠（范围 11.1-37.6 分钟）的时间。s-CAM 用于单牙种植体冠组件（基台/冠）的时间范围在 8.2 到 25 分钟之间。后处理（例如烧结）是一个耗时的过程（长达 530 分钟）。在交付时，整体式/贴面 CAD-CAM 种植体冠在椅旁（51%/93%）或实验室（11%/19%）需要额外的调整。
目前没有关于比较 s-CAM 和 a-CAM 的生产时间、效果和成本的数字化工作流程的科学证据。对于这两种技术，后处理过程可能会大大增加生产时间。考虑到效果，整体式 CAD-CAM 种植体冠可能优于贴面 CAD-CAM 冠。
