There is described a method for generating a 3D representation of an object, the method comprising retrieving a 3D structure representative of the object and comprising a plurality of voxels each having a respective position therein, each one of the voxels being shaped to mimic a shape of at least a portion of a potential internal feature for the respective position; receiving a densitometry measurement comprising densitometry data of the object; assigning a density value to each one of the voxels using the received densitometry data, thereby generating a 3D model of the object; and outputting the 3D model.