Caries imaging using T1 StarVIBE and PETRA sequences compared to normal dental work-up: a proof-of-concept study

To compare caries detection using T1-based Free-breathing 3D Stack of Stars GRE (StarVIBE) and T1-weighted pointwise encoding time reduction with radial acquisition (PETRA) MRI sequences with the gold standard consisting of a combination of clinical evaluation and bitewing radiography.

Included subjects were evaluated clinically by a dentist for the occurrence of caries. All subjects underwent bitewing radiographs and MRI of the viscerocranium, including 3D StarVIBE and 3D PETRA sequences. Caries lesions were evaluated for penetration depth (D1-D4). Signal intensity (SI) was measured in dental hard tissue, the pulp and caries lesions.

80 teeth were analyzed. Among these, 10 showed caries during clinical assessments and bitewing imaging, all of which were also detected on MRI. Furthermore, 5 additional lesions were identified exclusively on MRI. Overall image quality and diagnostic confidence were significantly higher in PETRA than in StarVIBE (4.7 vs. 3.9, p = 0.006). The SI for caries lesions was significantly higher in the PETRA sequence (-0.5 a.u. ± 1.5 a.u. vs. -4.2 a.u. ± 4.0 a.u., p = 0.002). Caries lesion volume was also significantly larger in PETRA (18 mm³± 14.8 mm³) compared to StarVIBE (11 mm³± 14.8 mm³, p = 0.003). CONCLUSION :  MRI identified all caries lesions that were detected both clinically and through bitewing imaging, along with additional lesions exclusive to MRI. The PETRA sequence outperformed StarVIBE in quantitative caries visualization.