Magnetic resonance imaging is used more and more frequently as a diagnostic tool, Because high magnetic fields are used, knowledge on how these will affect implanted material and the patient is of great importance. Ferromagnetic properties of implant materials are seldom described by the manufacturer, but a doctor requesting magnetic resonance imaging of a patient must know about these properties. Not only is the composition of an alloy important, but also the size and shape of the metallic material as well as its position in the body, Implants from the Branemark System were tested; findings indicated that the implants were not influenced when exposed to magnetic resonance imaging. The artifacts caused by the implants were minor and did not jeopardize the evaluation of the scans. However, magnet keepers attached to the implants were found to cause major artifacts and must be removed before an implant patient is referred for a magnetic resonance imaging examination.