Accuracy of digital impressions for implant‐supported complete‐arch prosthesis, using an auxiliary geometry part—An in vitro study

Abstract

Objectives The aim of this study was to evaluate the accuracy of complete‐arch digital impressions for fabrication of an implant‐supported prosthesis in the edentulous maxilla using an auxiliary geometry part. Materials and methods A replica of the upper jaw of an edentulous patient with four scannable impression copings was fabricated in stainless steel. This model was scanned with an industrial non‐contact 3D structured blue light 3D scanner, and the measurements of three reference distances were established as reference values. Subsequently, the model was scanned in two different scenarios (with or without an auxiliary geometry part put in place and fixed to the model) using three intraoral scanners. Measurements were taken with 3D inspection software, and a digital impression of the complete arch was built with mesh processing software by combining 2 STL files obtained with an intraoral scanner. Results All measurements with the auxiliary geometry part gave significantly more accurate results (p < .05). Trueness improved in the three reference distances, reaching values of 8 ± 6 µm at D12 reference distance, 20 ± 11 µm at D13 and 35 ± 22 µm at D14. Precision also improved significantly with the use of the auxiliary geometry part placed on the model (p < .05). The best precision results at reference distances D13 and D14 were obtained with the True Definition Scanner. Conclusions The proposed methodology significantly improves the accuracy of complete‐arch digital impressions in edentulous patients obtained in vitro, regardless of which scanner is used.

Use of measuring gauges for in vivo accuracy analysis of intraoral scanners: a pilot study

“…An edentulous jaw, presumably, would yield worse results, as has been mentioned in other literature. 8 31 …”

“…In contrast, IOS show high accuracy when scanning short span areas such as a tooth or a bridge up to half an arch. 5 6 7 8 …”

Accuracy Improvement of Intraoral Scanning and Buccal Bite Registration Using Healing Abutment as Landmarks: An In Vitro Study

“…This result may arise from the lack of stable features that could guarantee accurate stitching in an edentulous area [25]. The presence of auxiliary geometric structures may enhance the outcomes of digital impressions of edentulous areas [21]. When compared with the partially edentulous groups, the presence of an HA provided more complex geometry features for scanners to detect and allowed images to be stitched together smoothly, resulting in a significant enhancement in the scanning accuracy.…”

“…Errors may occur when aligning images during scanning by an IOS if the digitized items are too simple [19], with the errors being lower when complex geometric items are added [20]. Another recent study found that the use of auxiliary geometric structures can enhance the outcomes of digital impressions of the edentulous maxilla [21].…”

An open-source multifunctional registration device for implant-supported complete dentures

“…[12][13][14] However, the inclusion of an auxiliary geometric device appears to improve precision. 15 This article describes a straightforward analog multifunctional registration, capturing implant positions, soft-tissue contours, anterior tooth position, occlusal vertical dimension, and centric occlusion in a few minutes. The resulting device can then be used in the dental laboratory to generate a cast mounted in the correct relationships for prosthesis fabrication.…”