High Spatiotemporal resolution dental MRI using disposable wireless Intraoral Coil

Dental imaging techniques like X-rays and cone-beam computed tomography (CBCT) are considered the clinical gold standards for evaluating dental structures. However, they come with risks associated with ionizing radiation, such as DNA damage and a higher likelihood of cancer, as well as limitations in visualizing soft tissues. In this study, we present a high spatiotemporal resolution dental magnetic resonance imaging (MRI) framework that leveraged non-ionizing radiation to achieve superior soft tissue visualization without compromising diagnostic quality. Central to this framework is a novel wireless braced intraoral coil (WBIC), designed to be ultralight (<4 g), low-cost (~$70), and practical for clinical use. Electromagnetic field simulations were performed to optimize the coil’s performance, followed by experimental validation that demonstrated up to 6.8-fold improvements in signal-to-noise ratio (SNR) using a 48-channel head coil with the WBIC compared to the only head coil, allowing for detailed imaging of the dental pulp, root canals, and periodontal membrane. In the phantom studies, the WBIC system accurately resolves micro-defects as small as 200 μm, revealing structural details that are indistinct or entirely invisible in CBCT. In the in-vivo studies, a reconstruction method using deep learning-based auto-calibrating compressed sensing or diffusion-model-based compressed sensing integrated with the WBIC significantly speeded up the imaging process. High-fidelity imaging of periodontal membranes with anatomical thicknesses ranging from 0.15 mm to 0.38 mm was achieved, as well as gingival micro structure down to 200 μm. Compared to CBCT, the high spatiotemporal resolution dental MRI framework provided significantly enhanced visualization of both hard and soft tissue structures, particularly for gingival and other soft tissue regions where conventional methods fail. It also enabled comprehensive full-arch imaging of both single- and multi-rooted teeth in the maxilla and mandible, marking a significant advancement in dental MRI technology. This study has established a new benchmark for high-resolution, radiation-free dental imaging with broad applications in orthodontics, implantology, and periodontology.