The impact of dental impression materials on metal artifacts in cone beam computed tomography examination

To estimate the impact of different dental impression materials on cone beam computed tomography (CBCT) metal artifacts at different resolutions and fields of view (FOVs).

A mandible model with restored human teeth was created. Six dental materials were molded as teeth overlays with uniform thickness: A-silicones (Elite HD + , and Vonflex S Putty), Alginate (Tropicalgin), Pink wax (MBwax1), C-Silicon (Zetaplus) and Zinc-oxide (COE-PAK). The model alone (control) and with teeth covered with each material was scanned using CBCT Unite KAVO dent at two different FOVs-5 × 5 (S) and 6 × 8 cm (M), and three different resolutions: low (0.28-S; 0.32-M), standard (0.20-S; 0.30-M), and high (0.125-S; 0.20-M). Two experienced radiologists analyzed a single representative view of each dataset in ImageJ quantitatively-by conducting a histogram analysis within the selected regions of interest (ROI) and qualitatively (using a five-point Likert scale). The data were analyzed using standard one-way analysis of variance (ANOVA). Inter-rater reliability was examined.

The intraclass correlation coefficient for all quantitative measurements was between 0.806 and 0.996. Within FOV S, Vonflex S Putty showed significantly lower variance and range in grayscale values compared to the control at all resolution levels, while Zetaplus followed the same trend only at low resolution. As for FOV M, none of the tested materials significantly differed from the control in both variance and range. The qualitative analysis showed no significant differences when using overlays in comparison with uncovered teeth.

Although without significant improvements in the image quality, covering teeth with dental materials quantitatively reduced artifacts.