Dentures (clinically known as dentures) that cannot be examined by magnetic resonance mainly include metal crowns and porcelain crowns. Magnetic resonance is one of the common clinical examinations, which mainly utilizes the principle of magnetic resonance to scan various parts of the body and generate images for physicians’ reference and diagnosis; however, ordinary metal will produce thermal effect, strong adsorption and affect the diagnosis of the shortcomings in magnetic resonance, so it is not advisable to bring metal substances for magnetic resonance examination. All dentures containing metal (e.g. metal crowns or porcelain crowns) are made of common metal materials, so the above denture restorations are not suitable for MRI; it is recommended to ask the dentist to remove the denture and then conduct the MRI examination, and the dentist must be informed of this in advance, and it is not advisable to conceal the condition in order to prevent any accidents.