title: Repeatability and reproducibility of individual abutment impression, assessed with a blue light scanner.
abstract: OBJECTIVE
  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.
  
  
  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).
  
  
  CONCLUSIONS
  Our results indicated that impressions of individual abutment teeth, digitized with a blue light scanner, had good repeatability and reproducibility.
authors.affiliation: Department of Dental Technology, Medical campus, KyungDong University, Wonju, Republic of Korea.
authors.forename: Jin-Hun
authors.identifier: 0000-0003-2833-8946
authors.initials: JH
authors.lastname: Jeon
authors.affiliation: Department of Dental Laboratory Science and Engineering, College of Health Science, Korea University, Seoul, Republic of Korea.
authors.forename: Dong-Yeon
authors.initials: DY
authors.lastname: Kim
authors.affiliation: Department of Dental Laboratory Science and Engineering, College of Health Science, Korea University, Seoul, Republic of Korea.
authors.forename: Jae-Jun
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Department of Dental Laboratory Science and Engineering, College of Health Science, Korea University, Seoul, Republic of Korea.
authors.forename: Ji-Hwan
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Dental Laboratory Science and Engineering, College of Health Science, Korea University, Seoul, Republic of Korea.
authors.forename: Woong-Chul
authors.identifier: 0000-0002-6730-4960
authors.initials: WC
authors.lastname: Kim
keywords: Blue light scanner; Color-difference-map; Repeatability; Reproducibility