Enhancing the accuracy of full-arch digital implant impressions via segmentation: An in vitro study

The aim of this in vitro study was to assess whether the accuracy (trueness and precision) of full-arch implant digital impressions can be improved by replacing standard digital impressions (StDIs) with segmented digital impressions (SgDIs), obtained by superimposing short-span digital impressions using a geometric pattern.

The study was conducted using a commercial edentulous maxillary model with four implants-positioned at the sites of the canines and second molars-and four commercial intraoral scan bodies (ISBs) screwed to them. Ten StDIs and SgDIs of the model were obtained, and their accuracy was evaluated and compared in terms of trueness and precision, based on measurements of three distances and three angles between the ISBs.

The results of this study indicated that the SgDIs were significantly more accurate than the StDIs. The trueness and precision of the three distances measured in the SgDIs were better than those of the distances measured in the StDIs, in a statistically significant way. The trueness and precision of the angles measured in the SgDIs were, in general, also better than those of the angles measured in the StDIs, but in this case the differences were not statistically significant for all the measured angles.

Based on the results of this study, it was concluded that improving the accuracy of full-arch digital implant impressions through segmentation is feasible, even showing that accuracy values compatible with a passive fit of implant-supported full-arch prostheses can be achieved.