Purpose: The purpose of this study was to analyze the effect of scanning modes on the accuracy

of the Trios for full-arch digital implant impressions. Materials and Methods: The trueness and

precision of the intraoral scanning mode (IOSM) and the intraoral edentulous scanning mode

(IOEM) of the Trios were evaluated in three edentulous models, each featuring 4, 6, and 8

implant analogues. Reference scanning data were obtained by scanning each model with a

desktop scanner. Each model was scanned 10 times using the IOSM and IOEM modes of the

Trios to establish the test groups. The scan bodies in the test and reference scans were isolated

and exported in the reverse engineering program. The scan bodies in each group were

superimposed with the corresponding reference scan (trueness) or with each other (precision).

The overall 3D deviation between the aligned scan bodies was computed by the root-meansquare

(RMS) values. Results: As a result of the trueness and precision evaluation, no significant

difference was found between scanning modes in any of the models. When comparing models,

the 8-implant model showed significantly lower trueness than the 4-implant model. However, it

also exhibited significantly higher precision when compared to both the 4-implant and 6-implant

models. There were no significant differences in other pairwise comparisons between the

models. Conclusion: Trueness and precision values were similar between the IOSM and IOEM

groups across all the models. An increase in the number of implants in complete edentulous

arches may have a negative impact on digital impression accuracy.