Aim: To compare non-contrast-enhanced dental magnetic resonance imaging (NCE-dMRI) and cone-beam computed tomography (CBCT) in assessing horizontal and vertical furcation defects in maxillary molars in vivo.

Materials and methods: (NCE-dMRI) and CBCT were performed in 23 patients with severe periodontitis. Sixty-five first/second maxillary molars (195 furcation entrances) were analysed by two independent observers on both modalities to assess the horizontal and vertical components of furcation defects. Reliability of defect classification was evaluated using weighted kappa (κ) statistics. Agreement between NCE-dMRI and CBCT was determined by the Bland-Altman analysis. Sensitivity and specificity of NCE-dMRI were calculated using CBCT as the reference.

Results: Inter-radicular bone loss was observed in 94 furcation entrances. Intra- and inter-rater κ-values were ≥0.9 for both NCE-dMRI and CBCT. The Bland-Altman analysis showed mean differences (95% limits of agreement) of 0.12 mm (-0.67 to 0.90) for horizontal and 0.12 mm (-1.27 to 1.50) for vertical measurements. For the detection of furcation defects, sensitivity/specificity of NCE-dMRI was 98%/100% for horizontal and 99%/99% for vertical components. For defect classification, sensitivity values of NCE-dMRI were 88%/89%/100% (horizontal degree I/II/III) and 95%/91%/80% (vertical subclass A/B/C), respectively.

Conclusions: Non-contrast-enhanced dental magnetic resonance imaging demonstrated high reliability and high agreement with CBCT for the assessment of furcation defects in maxillary molars.