A method for obtaining a panoramic image similar to a panoramic radiography obtained from a patient through X-ray emission by processing an acquired 3D digital volume in voxel, each voxel having values of X-ray absorption is characterized by selecting a curved surface in 3D volume and identifying a plurality of first points on the curved surface and connecting each point of the identified first points with a corresponding pixel of the panoramic image to be obtained in order to map the first points of the curved surface on corresponding pixels of the panoramic image. Each identified point of the first points are associated with a respective set of lines passing through the identified point, each line having a different angle of incidence. The lines are contained in a solid angle having identified point as a vertex. An absorption value is calculated in the 3D volume along each of the lines. The identified point of the first points is attributed with an absorption value calculated as a function of all of the absorption values calculated for each of the lines of the set. The pixel linked to the identified point of the first points is attributed with a value expressed in grayscale calculated as a function of the absorption value of the identified point.
