PURPOSE
This study aimed to investigate whether the accuracy of intraoral scanners is influenced by different scanning strategies in an
in vitro
setting, through a systematic review and meta-analysis.
MATERIALS AND METHODS
This review was conducted in accordance with the PRISMA 2020 standard. The following PICOS approach was used: population, tooth impressions; intervention, the use of intraoral scanners with scanning strategies different from the manufacturer’s instructions; control, the use of intraoral scanners following the manufacturers’ requirements; outcome, accuracy of intraoral scanners; type of studies,
in vitro
. A comprehensive literature search was conducted across various databases including Embase, SciELO, PubMed, Scopus, and Web of Science. The inclusion criteria were based on
in vitro
studies that reported the accuracy of digital impressions using intraoral scanners. Analysis was performed using Review Manager software (version 5.3.5; Cochrane Collaboration, Copenhagen, Denmark). Global comparisons were made using a standardized mean difference based on random-effect models, with a significance level of α = 0.05.
RESULTS
The meta-analysis included 15 articles. Digital impression accuracy significantly improved under dry conditions (
P
< 0.001). Moreover, trueness and precision were enhanced when artificial landmarks were used (
P
≤ 0.02) and when an S-shaped pattern was followed (
P
≤ 0.01). However, the type of light used did not have a significant impact on the accuracy of the digital intraoral scanners (
P
≥ 0.16).
CONCLUSION
The accuracy of digital intraoral scanners can be enhanced by employing scanning processes using artificial landmarks and digital impressions under dry conditions.