Magnetic Resonance Imaging, or MRI, uses strong magnetic fields and radio waves to create detailed images of organs and tissues inside the body. The procedure is non-invasive and effective, but it requires a strictly metal-free environment to ensure patient safety and image quality. Because many dental appliances, including dentures, contain various metallic components, they frequently become a safety question for patients preparing for a scan. The answer to whether you can wear dentures in an MRI is generally no, depending entirely on the materials used in the dental prosthetic.
The Primary Safety Concern
The most immediate safety risk stems from the intense magnetic field generated by the MRI scanner. Any ferromagnetic material—meaning it is strongly attracted to a magnet—can be pulled with significant force toward the center of the machine. This phenomenon, often called the “missile effect,” could turn a metal-containing denture into a rapidly moving projectile inside the scan room.
Another concern is the risk of localized heating caused by the radiofrequency (RF) pulses the MRI machine emits. Metallic components in dental appliances can act like tiny antennas, absorbing and amplifying this energy. This absorption can lead to a temperature increase in surrounding soft tissues, potentially causing thermal burns in the mouth. Removing all metal-containing oral appliances is a standard safety precaution.
How Metal Components Interfere
The composition of the denture determines the level of interference and risk. Conventional full dentures, often made entirely of acrylic resin and porcelain teeth, typically contain no metal and are considered safe for the MRI environment. These acrylic appliances do not react to the magnetic field and usually do not need to be removed unless sedation is planned, which requires a clear airway.
Conversely, partial dentures or older full dentures often incorporate various metals, such as clasps, wires, or a metal base for added strength. These metallic parts can be made from ferromagnetic alloys containing iron, nickel, or cobalt, which are highly reactive to the MRI magnet and pose the greatest risk. Other materials, like titanium, are considered non-ferromagnetic and do not pose a safety risk, but they can still cause problems with the image quality.
Effect on Diagnostic Image Quality
Even if a metallic component does not pose a physical safety risk, its presence compromises the diagnostic quality of the scan. Metal causes a distortion in the local magnetic field uniformity, which the MRI machine relies on to create clear pictures. This distortion results in a magnetic susceptibility artifact.
These artifacts appear on the final image as signal voids—large black areas where tissue information has been obscured—or as geometric distortions. If the scan is of the head, neck, or brain, a metal-containing denture can create artifacts large enough to conceal nearby anatomical structures. The image corruption may be severe enough that the radiologist cannot make a confident diagnosis, potentially causing the procedure to fail.
Patient Preparation and Removal Protocol
The safest course of action is to assume that all removable dental prosthetics must be taken out before the scan. This includes full dentures, partial dentures, and any other removable oral appliance, regardless of the patient’s certainty about its composition. This removal is a standard step in the pre-screening process for an MRI.
Patients should disclose all dental work and removable appliances to the MRI technologist before entering the scanning room. The technologist will review a detailed pre-screening questionnaire to identify potential risks, including the presence of metal. If you are unsure about the materials in your dentures, communicating with your dental provider ahead of time can help determine if the appliance contains high-risk ferromagnetic metals.