Generating a panoramic image of a patient’s oral cavity

A method for generating a panoramic image of a patient from a plurality of two-dimensional x-ray projection images of the patient, the method comprising:

• defining a focal curve relative to an oral cavity of the patient, the focal curve following a shape of a jawbone of the patient, the focal curve having at least a molar region and an incisal region, the focal curve having a predefined thickness that is greater than a size of teeth of the patient that are to be imaged;
• and
• acquiring the plurality of two-dimensional x-ray projection images of the patient along the focal curve by:
• rotating an x-ray source, an x-ray collimator, and a flat-panel x-ray detector around a head of the patient along a predefined trajectory relative to the patient, the x-ray collimator being positioned between the head of the patient and the x-ray source, the x-ray collimator having an x-ray aperture with a variable x-ray aperture size, the x-ray aperture defining an exposure region on the flat-panel x-ray detector, the exposure region having a variable exposure region size that corresponds to the variable x-ray aperture size;
• continuously varying a width of the x-ray aperture during the acquiring of the plurality of two-dimensional x-ray projection images, the x-ray aperture having a first width when the molar region is exposed, the x-ray aperture having a second width less than the first width when the incisal region is exposed;
• and
• continuously varying a horizontal extent of a readout region of the flat-panel x-ray detector such that the readout region is variably sized equal to or larger than the variable exposure region size during the acquiring of the plurality of two-dimensional x-ray projection images.

A computer-readable medium for generating a panoramic image of a patient from a plurality of two-dimensional x-ray projection images of the patient, the computer-readable medium storing instructions, that when executed by a computing unit, cause the computing unit to execute operations, the operations comprising:

• defining a focal curve relative to an oral cavity of the patient, the focal curve following a shape of a jawbone of the patient, the focal curve having at least a molar region and an incisal region, the focal curve having a predefined thickness that is greater than a size of teeth of the patient that are to be imaged;
• and
• acquiring the plurality of two-dimensional x-ray projection images of the patient along the focal curve by:
• rotating an x-ray source, an x-ray collimator, and a flat-panel x-ray detector around a head of the patient along a predefined trajectory relative to the patient, the x-ray collimator being positioned between the head of the patient and the x-ray source, the x-ray collimator having an x-ray aperture with a variable x-ray aperture size, the x-ray aperture defining an exposure region on the flat-panel x-ray detector, the exposure region having a variable exposure region size that corresponds to the variable x-ray aperture size;
• continuously varying a width of the x-ray aperture during the acquiring of the plurality of two-dimensional x-ray projection images, the x-ray aperture having a first width when the molar region is exposed, the x-ray aperture having a second width less than the first width when the incisal region is exposed;
• and
• continuously varying a horizontal extent of a readout region of the flat-panel x-ray detector such that the readout region is variably sized equal to or larger than the variable exposure region size during the acquiring of the plurality of two-dimensional x-ray projection images.