Dimensional accuracy of extrusion- and photopolymerization-based 3D printers: In vitro study comparing printed casts

Norbert Nestler; Christian Wesemann; Benedikt C Spies; Florian Beuer; Axel Bumann

doi:10.1016/j.prosdent.2019.11.011

Dimensional accuracy of extrusion- and photopolymerization-based 3D printers: In vitro study comparing printed casts

J Prosthet Dent. 2021 Jan;125(1):103-110. doi: 10.1016/j.prosdent.2019.11.011. Epub 2020 Feb 13.

Authors

Norbert Nestler¹, Christian Wesemann², Benedikt C Spies³, Florian Beuer⁴, Axel Bumann⁵

Affiliations

¹ Doctoral student, Campus Benjamin Franklin, Center for Dental and Craniofacial Sciences (CC3), Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany. Electronic address: norbert.nestler@charite.de.
² Graduate 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, Berlin, Germany.
³ Privatdozent, 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, 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, Mesantis 3D Dental Radiologicum, Clinic of Orthodontics, Berlin, Germany.

PMID: 32063385
DOI: 10.1016/j.prosdent.2019.11.011

Abstract

Statement of problem: Reliable studies comparing the accuracy of complete-arch casts from 3D printers are scarce.

Purpose: The purpose of this in vitro study was to investigate the accuracy of casts printed by using various extrusion- and photopolymerization-based printers.

Material and methods: A master file was sent to 5 printer manufacturers and distributors to print 37 identical casts. This file consisted of a standardized data set of a maxillary cast in standard tessellation language (STL) format comprising 5 reference points for the measurement of 3 distances that served as reference for all measurements: intermolar width (IMW), intercanine width (ICW), and dental arch length (AL). The digital measurement of the master file obtained by using a surveying software program (Convince Premium 2012) was used as the control. Two extrusion-based (M2 and Ultimaker 2+) and 3 photopolymerization-based printers (Form 2, Asiga MAX UV, and myrev140) were compared. The casts were measured by using a multisensory coordinate measuring machine (O-Inspect 422). The values were then compared with those of the master file. The Mann-Whitney U test and Levene tests were used to determine significant differences in the trueness and precision (accuracy) of the measured distances.

Results: The deviations from the master file at all 3 distances for the included printers ranged between 12 μm and 240 μm (trueness), with an interquartile range (IQR) between 17 μm and 388 μm (precision). Asiga MAX UV displayed the highest accuracy, considering all the distances, and Ultimaker 2+ demonstrated comparable accuracy for shorter distances (IMW and ICW). Although myrev140 operated with high precision, it displayed high deviations from the master file. Similarly, although Form 2 exhibited high IQR, it did not deviate significantly from the master file in the longest range (AL). M2 performed consistently.

Conclusions: Both extrusion-based and photopolymerization-based printers were accurate. In general, inexpensive printers were no less accurate than more expensive ones.

MeSH terms

Computer-Aided Design
Dental Impression Technique
Imaging, Three-Dimensional
Maxilla
Models, Dental*
Printing, Three-Dimensional*
Software