Digital impression accuracy of a novel scannable healing abutment: an in vitro study with three intraoral scanners

This in vitro study aimed to evaluate the digital impression accuracy of a novel scannable healing abutment (s-HA) compared to a conventional scan body (CSB) using three intraoral scanners (IOSs) on a single implant. A maxillary partially edentulous model with an implant analog in the right first molar site was fabricated. The model with the exposed analog was scanned using ATOS Q to obtain Standard Tessellation Language (STL) file as the reference model. After installation of the artificial gingiva, the CSB and the s-HA were scanned ten times using three IOSs: Primescan, Trios 4, and Aoralscan 3, resulting in 60 STL files as the test models. The test models were imported to exocad DentalCAD to obtain implant positions. After model processing, distance and angular deviations were calculated by superimposing the test models over the reference model in Geomagic Control X. Statistical analyses were performed with the Generalized Additive Models for Location, Scale, and Shape framework for trueness and precision (α = 0.05). For distance trueness, the s-HA exhibited lower deviation than the CSB with Primescan (p < 0.001) and Trios 4 (p = 0.003), but not with Aoralscan 3 (p = 0.200). For angular trueness, the s-HA showed lower deviation than the CSB with Primescan (p = 0.043), Trios 4 (p < 0.001), and Aoralscan 3 (p = 0.011). Primescan achieved the highest trueness paired with s-HA with distance deviation of 49.5 μm and angular deviation of 0.0737 degrees. In terms of precision, the s-HA significantly improved the angular precision of Trios 4 (p < 0.001). The s-HA showed higher digital impression accuracy than the CSB, and the results were influenced by the type of IOS used.