- Any metal implants incompatible with MRI (including dental bridges, crowns, retainers, orthodontic devices e.g. braces, IUDs, aneurysm clips or other devices, tattoos containing metallic ink, cardiac pacemakers, prosthetic hear valves, other prostheses, neurostimulator devices, implanted infusion pumps, exposure to shrapnel or metal filings, cochlear implants, etc.)