Accuracy of Conventional and Digital Workflows in Partially Edentulous Cases Restored with FPDs over Implants. A Systematic Review

Purpose: To compare conventional and digital workflows in terms of accuracy in partially edentulous cases restored with implant-supported restorations. Methods: An electronic search in the databases PubMed, Scopus, Web Of Science, and CENTRAL was conducted to identify relevant publications, comparing digital and conventional workflows in partially edentulous cases restored with implant-supported prostheses. Results: 18 articles were included in the systematic review. Ten of the studies were in-vitro, and eight were clinical. Sample sizes varied considerably from 20 to 100. In three studies, three implants were investigated, whereas, in all other instances, accuracy was evaluated on two implants. Substantial heterogeneity in the methodology of the selected studies is evident, which prevents summarising the accuracy outcomes. Conclusions: Digital impressions showed similar results in terms of accuracy compared to the conventional approach. There is a lack of uniform criteria for the tolerable misfit, which hampers the ability to transfer in-vitro results to clinical situations. A need for a standardised approach in the evaluation of impression and workflow accuracy is warranted to enable the systematisation and analysis of results from different studies.