Repeat fixation for medical procedures is accomplished using a non-invasive locator, specifically a bite plate. The bite plate has at least three fiducial markers on it. The fiducial markers may be LEDs, radiopaque markers for angiography or computerized tomography (CT) imaging or magnetic resonance markers for magnetic resonance (MR) imaging. By detecting the position of the markers, the position of features within the patient (such as a brain tumor or other intracranial target to which radiation is to be applied) can be determined with great precision. Since the bite plate has been molded to uniquely fit to the patient's teeth, it may be removed after an initial imaging of the patient. The bite plate may then be re-attached one or more times to the teeth and the location of the features will be in a known position relative to the sensed markers. The patient's position can then be adjusted in order to bring the features to a desired location, such as bringing an intracranial target to the isocenter of a planned application of radiation. Importantly, the bite plate is mechanically independent of any structures used for positioning (that is moving) the patient such that no error introducing forces or torques are applied to the bite plate by adjusting patient position.