A dental X-ray apparatus of the conical-beam digitized-tomography type includes: an X-ray generator emitting an X-ray beam towards an object and provided with a collimation element for collimating the emitted beam; an X-ray sensor having an active surface arranged opposite the generator; wherein the generator and the sensor can rotate simultaneously about a rotation axis, the sensor being oriented so that a longitudinal axis extending from the generator to the sensor through the rotation axis is perpendicular to the active surface of the sensor, the center of the sensor being transversally offset relative to the projection of the axis on the sensor's active surface, the arrangement of the collimation element and the sensor thus offset defining that the collimated beam illuminates the sensor's active surface while leaving a peripheral area of the surface that is faintly illuminated by the collimated beam relative to the rest of the active surface.