Does ambient light affect the accuracy and scanning time of intraoral scans?

Christian Wesemann; Henriette Kienbaum; Magdalena Thun; Benedikt C Spies; Florian Beuer; Axel Bumann

doi:10.1016/j.prosdent.2020.03.021

Does ambient light affect the accuracy and scanning time of intraoral scans?

J Prosthet Dent. 2021 Jun;125(6):924-931. doi: 10.1016/j.prosdent.2020.03.021. Epub 2020 May 30.

Authors

Christian Wesemann¹, Henriette Kienbaum², Magdalena Thun², Benedikt C Spies³, Florian Beuer⁴, Axel Bumann⁵

Affiliations

¹ Research Associate, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders and Department of Orthodontics, Dentofacial Orthopedics and Pedodontics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany. Electronic address: christian.wesemann@charite.de.
² Doctoral student, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health and Mesantis 3D Dental-Radiology, Berlin, Germany.
³ Associate Professor, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
⁴ Professor and Chair, Department of Prosthodontics, Geriatric Dentistry and Craniomandibular Disorders, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
⁵ Professor and Director of 3D Imaging, Mesantis 3D Dental-Radiology, Berlin, Germany.

PMID: 32487348
DOI: 10.1016/j.prosdent.2020.03.021

Abstract

Statement of problem: Intraoral scanners (IOSs) are based on light-optical imaging methods. However, little is known about whether the ambient light in dental practices influences the accuracy and scanning time of the IOS.

Purpose: The purpose of this in vitro study was to investigate the influence of different illuminations on the accuracy of 4-unit and complete-arch scans of 6 IOSs. In addition, the required scanning time was evaluated.

Material and methods: A reference structure was attached to the first premolars (P) and second molars (M) in both quadrants (L/R) of a maxillary model. The resulting measured distances were M1-P1, M2-P2, P1-P2, and M1-M2. The investigation included 6 IOSs: TRIOS 3 (TRI), Cerec Omnicam (OC), iTero Element (ITE), CS 3600 (CS), Planmeca Emerald (EME), and GC Aadva (AAD). With each IOS, 17 scans at different illuminances (100, 500, 1000, and 5000 lux) were performed (N = 408). The precision and trueness for all distances were determined, and the scanning time was recorded. For statistical analyses, the Levene tests (precision) and 1-way analysis of variance with the post hoc Tukey honestly significant difference and Games-Howell tests (trueness) were calculated.

Results: Illuminance significantly influenced the trueness of 4-unit scans for OC, EME, and AAD. TRI, OC, ITE, and CS demonstrated comparable results. AAD (>96 ±22 μm; 1000 lux) and EME (>248 ±88 μm; 500 lux) revealed greater deviations. For complete-arch scans, illuminance did not influence TRI and AAD, but significant variations were detected for ITE, CS, EME, and AAD. The least deviations were achieved with TRI and OC. The scanning time was extended for all IOSs except ITE at more than 500 lux. The shortest scanning times with OC and EME were recorded at 100 lux; with TRI, CS, and AAD at 500 lux; and with ITE at both 100 and 5000 lux. At all illuminances, the fastest scans were obtained with TRI.

Conclusions: Ambient light was found to influence the accuracy and scanning time of IOSs. This influence varies depending on the device. For 4-unit scans, the effect was not clinically relevant, but for complete-arch scans, accuracy and scanning time can be improved with appropriate lighting.

MeSH terms

Computer-Aided Design
Dental Arch
Dental Impression Technique*
Imaging, Three-Dimensional
Models, Dental*