Effect of Scan Body Geometry and CAD Software on the Accuracy of Implant-Position Transfer: An In Vitro Study

Accurate transfer of implant position to the virtual model is essential for digital implant prosthodontic workflows. Although scan body geometry and CAD software may affect this process, evidence regarding their combined effect remains limited. This in vitro study evaluated the effects of two scan body systems and three CAD software programs on implant-position transfer accuracy and assessed their interaction. An edentulous maxillary titanium model with three implants was digitized ten times for each of two scan body systems. Each data set was processed with exocad, 3shape, and DWOS. Implant-position transfer was assessed as the three-dimensional Euclidean deviation of standardized scan body reference points. Data were analyzed using a two-way mixed repeated-measures ANOVA and Holm-adjusted pairwise comparisons (α = 0.05). Scan body system, CAD software, and their interaction significantly affected transfer accuracy (p < 0.001). Medentika showed lower mean deviations than NT-Trading with all software programs, although the difference was not significant with 3shape. For NT-Trading, 3shape produced significantly lower deviations than exocad and DWOS, whereas for Medentika, exocad produced significantly lower deviations than DWOS, with no significant differences between 3shape and either exocad or DWOS. Implant-position transfer accuracy depended on the specific combination of scan body system and CAD software. These findings suggest that scan body system and CAD software should be considered jointly when evaluating implant-position transfer accuracy.