Magnetic resonance imaging (MRI) is widely used as an essential imaging modality for diagnosis in dentistry and medicine. MRI is noninvasive and does not require exposure to any ionizing radiation. This is in contrast to X-ray computed tomography, X-ray angiography, and positron emission tomography (PET) by gamma rays. MR can create high-quality images of detailed anatomical structures because of its excellent soft tissue resolution. Applications of MRI include imaging blood vascular systems without a contrast medium, functional imaging of brain activity, spectroscopy, and fractional anisotropy. In clinical dentistry, MRI is used for the diagnosis of oral and maxillofacial diseases, especially tumors or temporomandibular disorders. Research on MRI use in dentistry has emphasized the areas of endodontics, orthodontics, and dental radiology.