Most metal implants typically do not cause problems. This is because most alloys used in orthopaedic and dental implants are not ferromagnetic. These include hip and knee replacements; plates, screws, and rods used to treat fractures; and cavity fillings. All of these metal implants can distort the MRI image if near the part of the body being scanned, but they will usually not cause problems to the equipment. It would be important to inform the technician performing the MRI scan that the plates exist.