J Adv Prosthodont.  2016 Jun;8(3):214-218. 10.4047/jap.2016.8.3.214.

Repeatability and reproducibility of individual abutment impression, assessed with a blue light scanner

• Jeon JH
• Kim DY
• Lee JJ
• Kim JH
• Kim WC

• KMID: 2376846
• DOI: http://doi.org/10.4047/jap.2016.8.3.214

Abstract

PURPOSE
We assessed the repeatability and reproducibility of abutment teeth dental impressions, digitized with a blue light scanner, by comparing the discrepancies in repeatability and reproducibility values for different types of abutment teeth.
MATERIALS AND METHODS
To evaluate repeatability, impressions of the canine, first premolar, and first molar, prepared for ceramic crowns, were repeatedly scanned to acquire 5 sets of 3-dimensional data via stereolithography (STL) files. Point clouds were compared and the error sizes were measured (n=10, per type). To evaluate reproducibility, the impressions were rotated by 10-20° on the table and scanned. These data were compared to the first STL data and the error sizes were measured (n=5, per type). One-way analysis of variance was used to assess the repeatability and reproducibility of the 3 types of teeth, and Tukey honest significant differences (HSD) multiple comparison test was used for post hoc comparisons (α=.05).
RESULTS
The differences with regard to repeatability were 4.5, 2.7, and 3.1 µm for the canine, premolar, and molar, indicating the poorest repeatability for the canine (P<.001). For reproducibility, the differences were 6.6, 5.8, and 11.0 µm indicating the poorest reproducibility for the molar (P=.007).
CONCLUSION
Our results indicated that impressions of individual abutment teeth, digitized with a blue light scanner, had good repeatability and reproducibility.

Keyword

Blue light scanner; Repeatability; Reproducibility; Color-difference-map

MeSH Terms

Bicuspid
Ceramics
Crowns
Molar
Tooth
Ceramics

Figure

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  Fig. 1 Scheme showing the experimental design.

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  Fig. 2 Resin tooth abutments. (A) Canine (#13), (B) Premolar (#14), (C) Molar (#16).

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  Fig. 3 Evaluation of the repeatability and reproducibility of digitized impressions obtained with a blue light scanner for three types of abutment teeth.

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  Fig. 4 Box plot showing the repeatability and reproducibility of impressions digitized with a blue light scanner for three types of abutment teeth; repeatability (n = 10 per type), reproducibility (n = 5 per type).

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