Accuracy of digital impressions in edentulous arches for implant-supported prostheses: An in vitro comparison

Accurate impressions are essential for the success of implant-supported prostheses, yet capturing edentulous arches remains challenging due to mucosal support and anatomical variability. This in vitro study compared the accuracy of conventional open-tray impressions with two intraoral scanners (IOS) in maxillary and mandibular edentulous models with six implant analogs. Ten impressions per group were analyzed by superimposing STL files and stone casts against a reference model to measure linear and angular deviations. Results showed significantly lower deviations in both digital groups compared to conventional impressions, with no significant difference between the two IOS types. These findings indicate that intraoral scanners provide superior accuracy and represent a clinically viable alternative for full-arch implant rehabilitations.