ObjectiveTo assess the efficacy of the metal artifact reduction algorithm (MARA) of the Cranex 3D cone beam computed tomography (CBCT) device in the detection of peri-implant dehiscence and fenestration around zirconia implants. Study designIn total, 60 implants were placed in bovine ribs. Dehiscence and fenestration defects were created around the implants, after which 60 CBCT images were obtained with and 60 without activation of MARA. Three radiologists examined the images for the presence of defects. The area under the curve (AUC) from receiver operating characteristic analysis, sensitivity, and specificity were calculated to assess the ability to discriminate the presence vs. absence of bone defects. One-way analysis of variance was employed to analyze outcomes measures. The significance level was established at 5% (α = 0.05). ResultsAUC values indicated excellent discrimination of dehiscence on images with MARA activation and an excellent to outstanding range of discrimination with MARA deactivation. For fenestration, MARA activation and deactivation both led to outstanding discrimination. Sensitivity and specificity values revealed that activation of MARA was helpful in distinguishing the presence vs. absence of dehiscence, while both MARA conditions were helpful for fenestration. However, there were no statistically significant differences between MARA activation and deactivation for any outcome measure (P>0.05). ConclusionCBCT is suitable for detecting peri-implant defects, but MARA application does not significantly affect peri-implant dehiscence and fenestration detection. Statement of Clinical RelevanceEarly diagnosis of defects in cortical bone around zirconia dental implants is important for maintaining function and aesthetics. Cone beam computed tomography is suitable for detecting peri-implant defects, but metal artifact reduction algorithms do not significantly affect diagnostic outcomes.