A sensor that is at least partially covered by a sheath, and a positioning arm that is electrically coupled to the sensor, and arranged outside of the sheath, such that a hygienic barrier is formed around the sensor. The sensor is used for filmless dental radiography and the positioning arm enables positioning of the sensor in a patients mouth. The positioning arm includes a contact that pierces the sheath and establishes an electrical connection with the sensor when the positioning arm is coupled to the sensor.
