Evaluation and Comparison of the Precision of Dental Implant Impressions and the Marginal Fit of Crowns Using Conventional and Digital Methods: A Clinical Study.

Background Accurate impressions are essential for the long-term success of implant-supported restorations. Both conventional and digital techniques are routinely used in clinical implantology, each with its own advantages and limitations. This study aimed to evaluate and compare the precision of digital and conventional implant impressions and compare the marginal fit of crowns obtained from digital impressions and those obtained from conventional impressions. Methodology This prospective, comparative, clinical study was conducted at the Department of Prosthodontics between January and December 2024. A total of 36 subjects with single-unit implants were included in this study. Digital impressions (n = 18) were obtained using a calibrated intraoral scanner (3Shape Trios 4, Copenhagen, Denmark), and conventional impressions (n = 18) were made with polyvinyl siloxane using a closed-tray technique and scanned using a laboratory scanner (Medit T310 D, Medit Corp., Seoul, South Korea). Both generated Standard Tesselation Language files were analyzed for precision using Geomagic Control 2014 version 2.0 software (3D Systems, Rock Hill, SC, USA) via best-fit alignment. The crowns were designed in Exocad, fabricated via direct metal laser sintering, and assessed for marginal fit using the silicone replication technique under a stereomicroscope at 40× magnification. Data were analyzed using one-way analysis of variance for intragroup comparisons and independent t-tests for intergroup comparisons (p < 0.05). Results Precision analysis indicated no significant difference between the conventional and digital methods (p = 0.672), despite the greater variability in the digital group. Intragroup analysis revealed no significant differences in marginal discrepancy across the four sites (distobuccal, mesiobuccal, distolingual, and mesiolingual) between the conventional and digital groups (p > 0.05). Intergroup comparisons revealed no significant differences in marginal discrepancies between the groups at all sites (p > 0.05). Conclusions Conventional and digital impression techniques demonstrated comparable precision and marginal fit for single-unit implant restorations and achieved clinically acceptable outcomes. Further research is warranted to explore multi-unit restorations and long-term clinical outcomes.