Influence of scanning protocol on the accuracy of complete‐arch digital implant scans: An in vitro study.

Objective: This in‐vitro study assessed the influence of two intraoral scanning (IOS) protocols on the accuracy (trueness and precision) of digital scans performed in edentulous arches. Methods: Twenty‐two abutment‐level master casts of edentulous arches with at least four implants were scanned repeatedly five times, each with two different scanning protocols. Protocol A (IOS‐A) consisted of scanning the edentulous arch before inserting the implant scan bodies, followed by their insertion and its subsequent digital acquisition. Protocol B (IOS‐B) consisted of scanning the edentulous arch with the scan bodies inserted from the outset. A reference scan from each edentulous cast was obtained using a laboratory scanner. Trueness and precision were calculated using the spatial fit analysis, cross‐arch distance, and virtual Sheffield test. Statistical analysis was performed using generalized estimating equations (GEEs). Statistical significance was set at α =.05. Results: In the spatial fit test, the precision of average 3D distances was 45 μm (±23 μm) with protocol IOS‐A and 25 μm (±10 μm) for IOS‐B (p <.001), and the trueness of average 3D distances was 44 μm (±24 μm) with protocol IOS‐A and 24 μm (±7 μm) for IOS‐B (p <.001). Cross‐arch distance precision was 59 μm (±53 μm) for IOS‐A and 41 μm (±43 μm) for IOS‐B (p =.0035), and trueness was 64 μm (±47 μm) for IOS‐A and 50 μm (±40 μm) for IOS‐B (p =.0021). Virtual Sheffield precision was 286 μm (±198 μm) for IOS‐A and 146 μm (±92 μm) for IOS‐B (p <.001), and trueness was 228 μm (±171 μm) for IOS‐A and 139 μm (±92 μm) for IOS‐B (p <.001). Conclusions: The IOS‐B protocol demonstrated significantly superior accuracy. Placement of scan bodies before scanning the edentulous arch is recommended to improve the accuracy of complete‐arch intraoral scanning. [ABSTRACT FROM AUTHOR]