Comparison of Treatment Time for Single-Implant Crowns Between Digital and Conventional Workflows for Posterior Implant Restorations: A Randomized Controlled Trial

Purpose: To compare the treatment time of digital and conventional workflows for single-implant crowns, as well as prostheses made of polymer-infiltrated ceramic-network (PICN; Vita Enamic, Vita Zahnfabrik) and lithium disilicate (LS2; n!ce, Straumann). Materials and Methods: A total of 40 patients who needed a single-implant crown in posterior regions were considered and randomly divided into digital workflows (n = 20) that used an intraoral scanner (IOS; iTero Element 5D, Align Technologies) and conventional workflows (n = 20) that used polyether impressions (3M ESPE Impregum Penta). Then, each group was again distributed into two subgroups based on the crown material used: PICN (n = 10) and LS2 (n = 10). Treatment time was calculated for both digital and conventional workflows. Analysis was done at a 5% confidence interval (P < .05). An independent two-sample t test was used to compare treatment time between the groups. The Kruskal-Wallis test was used to compare clinical try-in time among subgroups. Any of the implant crowns that had to be remade in each subgroup were evaluated using the Fisher exact test. Results: The entire process of digital and conventional workflows required 104.31 +/- 20.83 and 153.48 +/- 16.35 minutes, respectively. Digital workflows saved 39.2% more time than the conventional protocol for the single-implant crown treatment (P < .0001). Conclusions: Both digital and conventional workflow protocols can achieve a successful outcome for single-implant monolithic crowns in posterior areas. The digital protocol yielded greater timesaving over the conventional procedure in data acquisition and laboratory steps, while the time for clinical try-in and delivery were similar.