A dental radiography device has an X-ray sensor (12) with a sensitive surface (22) for detecting X-rays and oriented towards the front face (16) of the sensor and a device for positioning the sensor made up of a receiver (32), for receiving the sensor, and an oblong arm (34) with an end (35) fixed to the receiver and an outwardly directed portion (34B) extending towards the front of the sensor and intended to extend out of the mouth of a patient, the receiver contained in a rear cylindrical space (33B) extending at the rear of a rear face (18) of the sensor opposite the front face (16), the rear cylindrical space (33B) defined by movement, along a lateral edge of the sensor, of a generating straight line (333) perpendicular to the sensitive surface.
