Metal artefact reduction improves cone-beam CT diagnosis of peri-implant bone defects regardless of adjacent implant position in endomass or exomass

Objectives To evaluate the influence of the position of an adjacent implant, either within the endomass or exomass, and the use of the metal artifact reduction (MAR) tool on the diagnosis of peri-implant bone defects associated with the surfaces of a zirconia implant in cone beam computed tomography (CBCT) images. Materials and Methods Ten bovine rib blocks were used to simulate a human mandible, each receiving two zirconia implants. CBCT images were acquired using the OP300 Maxio device (90 kVp, 6.3 mA, FOV 5 × 5 cm, voxel 0.125 mm) under two positions for the adjacent non-test implant (endomass and exomass), with and without MAR application, totaling 40 scans for the without peri-implant bone defects group. Circumferential bone defects were then created around the test implant, and 40 scans were acquired for the group with peri-implant bone defects under the same conditions. Four oral and maxillofacial radiologists individually evaluated each surface of the test implant for the presence of bone defect, using a 5-point scale. Weighted Kappa was used to assess intra- and interexaminer reproducibility. Diagnostic values were compared using multifactorial ANOVA (α = 0.05). Results In general, the position of the adjacent implant did not significantly affect the diagnostic values (p > 0.05). MAR significantly increased sensitivity and area under the ROC curve for most implant surfaces, particularly the mesial and distal surfaces, regardless of adjacent implant position (p < 0.05). Specificity remained high under all conditions. Intra- and interexaminer agreement ranged from fair to substantial. Conclusions Overall, adjacent implant position—whether within the endomass or exomass -, with an inter-implant distance of 5 mm, does not impact peri-implant bone defect diagnosis associated with a zirconia implant. MAR substantially improves the diagnosis of peri-implant defects on most implant surfaces, especially in the proximal area, regardless the adjacent implant position in the endomass or exomass.