A Pilot Comparative Study of Multi‐Contrast Dental <scp>MRI</scp> and <scp>CBCT</scp> : Clinical Correlates of Disease Status and Inflammatory Burden in Periodontitis

AIM: To evaluate the reliability of multi-contrast dental MRI (dMRI) for periodontal lesion assessment in comparison to cone-beam computed tomography (CBCT). Associations between imaging findings and clinical indicators of periodontal inflammation (i.e., bleeding on probing [BOP], periodontal probing depth [PPD] and periodontal inflamed surface area [PISA]) were analysed to explore the potential of dMRI to reflect disease status and inflammatory burden. MATERIALS AND METHODS: In this prospective study, patients with severe periodontitis underwent clinical examination, CBCT and 3T dMRI. Site-level detectability of periodontal osseous defects and/or marrow signal changes at the six standard clinical probing sites per tooth, as well as tooth-level lesion volumetry, were evaluated across CBCT, T1-weighted (T1W), contrast-enhanced T1W and T2-weighted (T2W). Reliability (κ, ICC) and clinical-imaging associations (Kruskal-Wallis and mixed-effect models) were analysed. RESULTS: Nineteen patients with severe periodontitis stages III and IV were included. Reliability of dMRI matched CBCT (site-level κ = 0.631-0.771; tooth-level ICC = 0.832-0.973). Increasing PPD and BOP raised lesion detectability and volumes across all modalities, with dMRI being consistently more sensitive than CBCT. T1W MRI showed lesions and bone loss similar to CBCT and was unaffected by BOP (p = 0.132) or PPD (p = 0.252). T2W MRI identified most lesions regardless of PPD and reflected high correlations with BOP (p < 0.05), PPD (p < 0.001) and PISA (p < 0.001). CONCLUSIONS: Reliability of dMRI for lesion identification and quantification was comparable to that of CBCT. The presence of T2W marrow oedema at sites with a CBCT-normal periodontal ligament space and no radiographically detectable bone loss may represent a promising imaging marker for early periodontal disease recognition and assessment of inflammatory burden.