Abstract
OBJECTIVE To identify clinical studies evaluating efficiency and/or effectiveness of digital technologies as compared to conventional manufacturing procedures for the fabrication of implant-supported reconstructions. MATERIALS AND METHODS A systematic search from 1990 through July 2017 was performed using the online databases Medline, Embase, and Cochrane-Central-Register-of-Controlled-Trials. Literature on efficiency and/or effectiveness during the impression session, the manufacturing process, and the delivery session were included. RESULTS In total, 12 clinical studies were included. No meta-analysis was performed due to a large heterogeneity of the study protocols. Nine publications reported on posterior single implant crowns (SIC) and three on full-arch reconstructions. Mean impression time with intraoral scanners ranged between 6.7 and 19.8 min, whereas the range for conventional impressions was 8.8 and 18.4 min. In a fully digital workflow (FD-WF) for posterior SIC, mean fabrication time ranged between 46.8 and 54.5 min (prefabricated abutment) and 68.0 min (customized abutment). In a hybrid workflow (H-WF) including a digitally customized abutment and a manual veneering, mean fabrication time ranged between 132.5 and 158.1 min. For a conventional porcelain-fused-to-metal-crown, a mean time of 189.8 min was reported. The mean time for the delivery of posterior SIC ranged between 7.3 and 7.4 min (FD-WF), 10.5 and 12.5 min (H-WF), and 15.3 min (conventional workflow, C-WF). The FD-WF for posterior SIC was more effective than the H-/C-WF. CONCLUSIONS The implementation of the studied digital technologies increased time efficiency for the laboratory fabrication of implant-supported reconstructions. For posterior SIC, the model-free fabrication, the use of prefabricated abutments, and the monolithic design was most time efficient and most effective.
Mühlemann, Sven