Comparison of Reproducibility of Linear Measurements on Digital Models among Intraoral Scanners, Desktop Scanners, and Cone-beam Computed Tomography

ABSTRACT

Purpose@#Intraoral scanners, desktop scanners, and cone-beam computed tomography (CBCT) are being used in a complementary way for diagnosis and treatment planning. Limited patient-based results are available about dimensional reproducibility among different three-dimensional imaging systems. This study aimed to evaluate dimensional reproducibility among patient-derived digital models created from an intraoral scanner, desktop scanner, and two CBCT systems. @*Materials and Methods@#Twenty-nine arches from sixteen patients who were candidates for implant treatments were enrolled. Different types of CBCT systems (KCT and VCT) were used before and after the surgery. Polyvinylsiloxane impressions were taken on the enrolled arches after the healing period. Gypsum casts were fabricated and scanned with an intraoral scanner (CIOS) and desktop scanner (MDS). Four test groups of digital models, each from CIOS, MDS, KCT, and VCT, respectively, were compared to the reference gypsum cast group. For comparison of linear measurements, intercanine and intermolar widths and left and right canine to molar lengths were measured on individual gypsum cast and digital models. All measurements were triplicated, and the averages were used for statistics.Bland–Altman plots were drawn to assess the degree of agreement between each test group with the reference gypsum cast group. A linear mixed model was used to analyze the fixed effect of the test groups compared to the reference group (α=0.05).Result: The Bland–Altman plots showed that the bias of each test group was –0.07 mm for CIOS, –0.07 mm for MDS, –0.21 mm for VCT, and –0.25 mm for KCT. The linear mixed model did not show significant differences between the test and reference groups (P>0.05). @*Conclusion@#The linear distances measured on the digital models created from CIOS, MDS, and two CBCT systems showed slightly larger than the references but clinically acceptable reproducibility for diagnosis and treatment planning.reproducibility for diagnosis and treatment planning.plots showed that the bias of each test group was –0.07 mm for CIOS, –0.07 mm for MDS,