J Dent Rehabil Appl Sci.  2019 Jun;35(2):55-63. 10.14368/jdras.2019.35.2.55.

A review on the accuracy assessment methods of 3-dimensional digital dental models

• Park JS
• Lim YJ
• Lee J
• Kim B

• KMID: 2451752
• DOI: http://doi.org/10.14368/jdras.2019.35.2.55

Abstract

The aim of this article was to review various methods used to evaluate the accuracy of digital dental models. When evaluating the accuracy of digital models, the errors can be reduced by educating examiners and using artificial landmarks. The accuracy evaluation methods of digital dental models are divided into linear measurement, 2-dimensional cross-sectional analysis, and 3-dimensional best fit measurement. As the technology of scanners develops, many studies have been conducted to compare the accuracy of digital impression and conventional impression. According to improvement of scan technologies and development of 3-dimensional model analysis software, the ability to evaluate the accuracy of digital models is becoming more efficient. In this article, we describe the methods for evaluating the accuracy of a digital model and investigate effective accuracy analysis methods for each situation.

Keyword

intraoral scanner; digital accuracy; linear measurement; cross-sectional analysis; best-fit algorithm

MeSH Terms

Cross-Sectional Studies
Dental Models*
Methods*

Figure

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  Fig. 1 Accuracy, which includes Trueness and Precision, is represented by the bias and standard deviation of the Total error.

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  Fig. 2 Linear measurements made on each digital model. (A) Incisor to molar, (B) Intermolar width, (C) Incisor height.

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  Fig. 3 Linear measurements at reference point of 3D model. a: inter-canine distance; b: inter-first molar distance; c:inter-second molar distance; d: arch length; e: first molar height; f: second molar height.

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  Fig. 4 Deviations after superimposition of scan datasets displayed in a color-coded using Best-Fit Alignment function in Geomagic Control XTM (3D systems, RockHill, USA).

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  Fig. 5 2-dimensional cross-sectional analysis of abutment tooth. (A) Buccal-Lingual section, (B) Mesial-Distal section, (C) Transverse High section, (D) Transverse Middle section, (E) Transverse Low section. B: buccal; L: lingual; M: mesial; D: distal.17

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  Fig. 6 Deviations after superimposition of edentulous scan datasets displayed in a color-coded difference image.

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  Fig. 7 Anatomical landmarks on a polished surface and a denture base surface.

Reference

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