Method and apparatus for acquiring volumetric CBCT radiographies in an apparatus having a rotary supporting arm, at the ends of which at least an X-ray source and at least an X-ray sensor are positioned, the supporting arm rotating the at least one source and the at least one sensor around a patient. The method includes the steps of positioning a patient on the positioning device, and acquiring a CBCT image through a trajectory having an angular extension lower than 360°, wherein the rotation center of the trajectory of the X-ray sensor is never on the median sagittal plane defined by the patient positioned inside the apparatus and the trajectory is not symmetric to any of the possible sagittal planes of the patient.
