A randomized clinical trial comparing the clinical fit and chairside adjustment time for implant-supported crowns fabricated by fully digital and partially digital techniques

Implant-supported crowns made in both fully and partially digital workflows have been evaluated, but these studies have been mainly performed in vitro. Moreover, data on the comparison of clinical fitting and adjustment time for implant-supported crowns are limited. The purpose of this randomized clinical trial was to evaluate the clinical fit and adjustment time for implant-supported crowns produced by a partially and fully digital workflow in partially edentulous participants. Twenty-eight participants who had received 2 adjacent implants in posterior sites were enrolled, each receiving 2 custom titanium abutments and a splinted monolithic zirconia restoration. Restorations of the control group (n=14) were produced from a digital scan and a cast-free digital workflow, while the restorations of the test group (n=14) were from a conventional impression and a partially digital workflow. A blinded investigator delivered the restorations. The clinical adjustment was performed incrementally, and a digital chronometer recorded the time required for the evaluation and adjustment at each step. An independent t test, Mann-Whitney U test, and the Fisher exact test were used to evaluate the results (α=.05). The total mean adjustment time in the control group (12.49 minutes) was significantly longer than that of the test group (11.27 minutes) (P.05). All crowns could be successfully delivered after 2 clinical appointments (impression and delivery). Remakes were not necessary for any restorations in the test or control group. The parameters of occlusal adjustment time and total adjustment time of the fully digital workflow were significantly shorter than those of the partially digital workflow.