Evaluation of the patient's perception, reliability and reproducibility, and chairside time with intraoral scanners in adult population—a systematic review

Introduction Digital impression techniques have gained popularity in dentistry due to their potential advantages in accuracy, efficiency, and patient comfort. This systematic review aims to evaluate and compare the accuracy, chairside time, and patient perception of conventional vs. digital impressions. Methods A systematic search was conducted in Medline/PubMed, EBSCO, Web of Science, and Scopus databases. Inclusion criteria comprised clinical or in vivo studies comparing conventional and digital impression techniques in terms of accuracy, working time, and/or patient comfort. Reviews, meta-analyses, editorials, and studies involving fully edentulous patients or edentulous spans exceeding two teeth were excluded. Study quality was assessed using the QUADAS−2 tool, and intra-operator agreement was evaluated using the Cohen's Kappa statistic. Results From 269 initially identified articles, 10 met the inclusion criteria. All studies assessed accuracy; only two evaluated working time and patient comfort. The included studies, published between 2016 and 2024, were cross-sectional observational in design, with sample sizes ranging from 5 to 50 participants. A variety of intraoral scanners were evaluated, including Cerec, Trios, iTero, and Primescan. The QUADAS-2 tool indicated an overall unclear risk of bias in patient selection and mixed concerns regarding applicability. While findings on accuracy were mixed, most studies concluded that both techniques are clinically acceptable, with conventional impressions performing better in full-arch cases. Digital impressions were consistently reported as faster and more comfortable for patients. Limitations The findings of this review should be interpreted with caution due to methodological heterogeneity, small sample sizes, and the inclusion of predominantly young, fully dentate participants. Conclusion Intraoral scanners offer advantages in workflow efficiency and patient experience, although conventional impressions remain reliable and widely used. The variability in study designs and outcome measures underscores the need for standardized evaluation protocols in future research. Systematic Review Registration https://doi.org/10.17605/OSF.IO/62RCY .