Accuracy of cone-beam computed tomography, dental magnetic resonance imaging, and intraoral radiography for detecting peri-implant bone defects at single zirconia implants-An in vitro study.

Abstract

To evaluate the diagnostic value of cone-beam computed tomography (CBCT), intraoral radiography (IR), and dental magnetic resonance imaging (dMRI) for detecting and classifying peri-implant bone defects at zirconia implants. Forty-eight zirconia implants were inserted in bovine ribs, 24 of which had standardized defects (1-wall, 2-wall, 3-wall, 4-wall) in two sizes (1 and 3mm). CBCT, IR, and dMRI were performed and analyzed twice by four readers unaware of the nature of the defects. Cohen's and Fleiss' kappa (κ), sensitivity, and specificity were calculated for the presence/absence of bone defects, defect size, and defect type. Cochran's Q-test with post hoc McNemar was used to test for statistical differences. A high intra- and inter-reader reliability (κ range: 0.832-1) and sensitivity/specificity (IR: 0.97/0.96; CBCT: 0.99/1; dMRI: 1/0.99) for bone defect detection were observed for all three imaging methods. For defect type classification, intra- (κ range: 0.505-0.778) and inter-reader (κ: 0.411) reliability of IR were lower compared to CBCT (κ range intrareader: 0.667-0.889; κ inter-reader: 0.629) and dMRI (κ range intrareader: 0.61-0.832; κ inter-reader: 0.712). The sensitivity for correct defect type classification was not significantly different for CBCT (0.81) and dMRI (0.83; p=1), but was significantly lower for IR (0.68; vs. CBCT p=0.003; vs. dMRI p=0.004). The sensitivity advantage of CBCT and dMRI for defect classification was smaller for 1-mm defects (CBCT/dMRI/IR: 0.68/0.72/0.63, no significant difference) than for 3-mm defects (CBCT/dMRI/IR: 0.95/0.94/0.74; CBCT vs. IR p=0.0001; dMRI vs. IR p=0.003). Within the limitations of an in vitro study, IR can be recommended as the initial imaging method for evaluating peri-implant bone defects at zirconia implants. CBCT provides higher diagnostic accuracy of defect classification at the expense of higher cost and radiation dose. Dental MRI may be a promising imaging method for evaluating peri-implant bone defects at zirconia implants in the future.