Summary: Introduction: The effort to exclude metals from stomatological treatment follows to continuing effort for development of new materials or application of materials from other branches. The fiber-reinforced com-posites háve been ušed in dental medicíně since the end of 80ies. They are composed from glass fibers embedded in a resin matrix. For splinting the materials háve been ušed in the form of strips which toughen during the application. Care report: The authors planned the magnetic resonance imaging of the head in the orthodontic patient for suspected neurological illness. In view of the character of the disease the physician was asked to finish the orthodontic examination as soon as possible and to dismantle the fixed orthodontic apparatus. As a retention device the authors made use of a strip from FRC materiál, which was not contraindicated for MR imaging in contrast to the conventional steel wire. Conclusion: With growing requirements to esthetic outcome the development of non-metal technologies has been increasing. The application of FRC materials for retention after orthodontic therapy has been gaining importance. In čase of MR imaging of the head is the use of non-metal materials of cardinal importance.

        Key words: retainer -. FRC materials - magnetic resonance