Abstract: Apparatus for taking dental x-rays used in performing subtraction radiography, includes an appliance for holding a dental x-ray film at a fixed position with respect to the teeth of a person, the appliance including a dental mold for holding the appliance in a fixed position on the teeth of the person, and a connecting member for holding the x-ray film in a fixed position relative to the teeth of the person and being mounted to the mold such that the x-ray film is positioned in the mouth at a set position; a magnetic source mounted at a fixed position in a room for producing a time-varying low frequency magnetic field; a magnetic sensor for sensing the magnetic field and for producing an output signal in response thereto, the magnetic sensor being mounted to the connecting member so as to be fixed in position relative to the x-ray film; an x-ray source for exposing the x-ray film; a robot manipulator having at least five degrees of freedom for moving the x-ray source in relation to the x-ray film, and having

Abstract: A method of optically mapping a person's face includes the steps of illuminating the face through a grid structure to produce a grid representation on the face; viewing the illuminated face with a video camera; producing a video signal in response to the step of viewing; converting the video signal to digital form; storing a frame of the digitized video signal in a frame memory; defining the grid representation on the face, from the stored video signal; locating coordinates of the intersection points of the grid representation; determining curvatures of the grid representation at the located intersection points; and three-dimensionally reconstructing the surface of the face from the coordinates and curvatures of the intersection points.

Abstract: Apparatus for measuring a volume change for facial swelling of a person which may occur after surgical removal of wisdom teeth, including a bite fork engageable within the mouth of the person for providing a relatively fixed reference position for the facial swelling; a reciprocable feeler rod having a free end with a feeler wheel secured thereto and reciprocable in a first x-axis direction substantially normal to the facial swelling; a spring which biases the feeler wheel into contact with the facial swelling; a tracing device for moving the feeler wheel in a second y-axis direction substantially normal to the first direction to cause the feeler wheel to trace across the facial swelling in a plurality of parallel planes spaced apart by a predetermined distance in the z-axis direction; a first LVDT for producing a first signal in response to the reciprocable movement of the feeler wheel in the first direction; a second LVDT for producing a second signal in response to movement of the feeler wheel in the secon