The effect of scanbody modifications on digital impressions onimplants on digital impression accuracy: In vitro study

There is not enough information in the literature on the effect of modifications made on the scanbodies used in the digital workflow of implant restorations on the impression accuracy. The aim of this study is to examine the effect of the modifications made on the digital impressions taken with different intraoral scanners on the impression accuracy. For this purpose, two implants were placed in the partial maxillary edentulous model produced by a 3D printer. In order to determine the three-dimensional position of the implants, scanning was performed with a laboratory scanner and a reference dataset was obtained. In the study, 4 groups were formed according to the modifications made to the scan bodies: Group 1; no modifications were made, Group 2; A 2x3 mm wide area was excised from the proximal surface, Group 3; A 3x4 mm wide area was excised from the proximal surface, Group 4; The 3x6 mm wide area covering part of the screw entry slot has been removed. Digital impressions were taken with three different intraoral scanners (Itero Element 2, 3shape Trios 4, Medit i500) in each group (n=10). The digital data obtained from intraoral scanners, the reference data set and the measurement precision were evaluated by using the mathematical registration algorithm program. Mann-Whitney U non-parametric statistical analysis test was used to evaluate the results. A statistically significant difference was found between the groups in both implant sites, independent of the intraoral scanner (p<0.05). While there was no significant difference between intraoral scanners in Groups 1 and 2 (p>0.05), a significant difference was found between scanners in Groups 3 and 4 (p<0.05). When the angular deviation values are examined, the statistical difference between the devices for both implant regions is not significant (p>0.05). Modifications made to the scanning bodies affect the measurement accuracy. The accuracy of intraoral scanners on the implant in partial edentulism is similar.