Comparison of the Clinical Accuracy of Digital and Conventional Dental Implant Impressions

Abstract

The aim of this study was to compare the clinical accuracy of digital and conventional dental implant impressions. Two types of implant impressions were made for each case, namely a conventional open-tray impression and a digital implant impression (DII) using a Trios IOS. Master casts were scanned using a D800 laboratory scanner and STL files were retrieved from conventional and digital workflows to be exported for comparison. The distance between center points, angulation, rotation, vertical shift, and surface mismatch of the scan bodies were evaluated and compared between conventional and digital impression techniques. Comparing digital and conventional impression techniques the following factors showed statistically significant differences: distance (73.7±75 μm), angulation (0.42±0.3°), and surface mismatch of scan bodies. The difference in conventional and digital impression techniques as regards to angulation and distance between the implants were associated with distance, angle, and vertical shift differences in scan. The mismatch of the scanned surface of scan bodies was twice higher for the intraoral scanner group. Clinicians should therefore control the implant suprastructures clinically and also using casts (e.g. printed casts) when a digital scan is planned.

Keywords: Conventional Impressions; Dental Implants; Digital Impression; Intraoral Scanner; Prosthodontics.