1. A medical imaging marker for use with imaging device, comprising: a base composed of a non-imageable material that is substantially invisible to the imaging device, the base having a front portion and a rear portion that is configured to fit into the mouth of a human patient; first and second spherical members provided in a predetermined positional relationship in the rear portion of the base and both composed of an imageable material; and a third spherical member provided in the front portion of the base in a predetermined positional relationship with the first and second spherical members, the third spherical member being composed of imageable material; first, second, and third auxiliary marker members provided in the base and composed of the imageable material, the auxiliary marker members having linear portions and each auxiliary marker member having a predetermined length sufficient to serve as a mark, wherein the first auxiliary marker member is disposed in the rear portion of the base and parallel to an axis extending through center points of the first and second spherical members, wherein the second auxiliary marker member is disposed parallel to an axis extending through center points of the second and third spherical members, and wherein the third auxiliary marker member is disposed parallel to an axis extending through center points of the third and first spherical members.