Analyzing the influence of scanning speeds and distances on digital intraoral scans: a systematic review and meta-analysis.

Objective: This study aimed to evaluate the influence of scanning speed and distance on the precision and quality of digital intraoral scans.

Data: The PICO strategy was employed to delineate the inclusion and exclusion criteria. The acquired records underwent filtration according to eligibility criteria, with essential information subsequently extracted. The meta-analysis, facilitated by Review Manager 5.4, utilized chi-square and the inconsistency index, along with forest plots. The standardized mean difference (SMD) was employed for the comparative analysis of study groups. Additionally, the study encompassed assessments of publication bias and the quality of included studies.

Sources: The search was conducted using three Internet databases: PubMed, ScienceDirect, and the Cochrane Library.

Results: Among the evaluated scanners (Trios 3, Trios 4, iTero, Primescan, Medit i500), only TRIOS 3 exhibited a statistically significant sensitivity to scanning parameters (SMD = -4.03; 95% CI: -7.26 to -0.80; P = 0.01). Increased scanning distances and faster speeds markedly reduced its accuracy, likely due to its older optical technology lacking real-time error correction features present in newer models like TRIOS 4 and Primescan. No significant effects were observed for TRIOS 4, Primescan, or Medit i500 (P > 0.05), suggesting their advanced hardware/software mitigates parameter variability.

Conclusions: Clinicians using TRIOS 3 should prioritize shorter scanning distances (5-10 mm) and slower speeds to optimize accuracy, as its performance is highly dependent on operator-controlled parameters. In contrast, newer scanners (e.g., TRIOS 4, Primescan) demonstrate greater resilience to distance/speed variations, enabling flexible clinical workflows. These findings underscore the importance of device-specific protocols to enhance digital impression reliability in restorative and prosthetic dentistry.