Effect of Phantom Containing Implants Angulation on the Amount of Metal Artifacts Around the Implants in CBCT Images

Artifacts from dental implants impact the clarity of cone-beam computed tomography (CBCT) scans, posing challenges to radiographic detection in adjacent areas. The aim of this in vitro study is to examine the effect of angling a phantom incorporating implant fixtures on the amount of metal artifacts in CBCT scans.

Three titanium fixtures, each with a diameter of 4.2 mm and a height of 12 mm were positioned within a bone block made of bovine mandibular bone. The specimen was placed on a surveyor table. The device was employed to regulate the rotation of the phantom along anterior-posterior (α) and right-left (β) axes. For each axis, the sample was scanned at three angles (0°, 15°, and 30°), resulting in a total of 12 scans. Each scan includes 10 regions of interest (ROIs). The absolute gray values (GVs) of all ROIs were determined at two levels (apical and coronal), and the mean and standard deviation (SD) were calculated. Using SPSS version 23 software, two-way ANOVA was employed to examine the impact of the angle and plane of rotation on the quantity of metal artifacts.

Higher ΔGV was seen as the angle increased in the alpha plane, while in the beta plane, the highest ΔGV occurred at 15°. At the apical level, mean ΔGV in the alpha plane (0.036) was higher than in the beta plane (0.007), whereas at the coronal level it was higher in the beta plane (0.186 vs. 0.087). Corresponding p-values for placement angle, rotation plane, and interaction of angle in the rotation plane were 0.734, 0.519, and 0.811 at the apical level and 0.254, 0.448, and 0.305 at the coronal level.

Altering the implant placement angle and rotation plane did not significantly impact the quantity of metal artifacts in CBCT images.