Abstract: A periodontal probe includes sequentially disposed, normally connected sensor, shaft and tip portions, and a longitudinally extending fiber element in the tip and shaft portions. The fiber element is retractable into the tip portion to measure the depths of periodontal pockets in the mouth of a patient, and the sensor portion is operative for generating electrical signals which cumulatively provide indications of the relative positions of the tip portion and the fiber element. The shaft portion, the tip portion and the fiber element are preferably disposable and detachably connected to the sensor portion so that they can be discarded after a single periodontal examination. The shaft portion and the tip portion preferably have a combined length of at least approximately 41/2 inches so that only the disposable portions of the probe normally come into contact with the hands of a dentist or the mouth of a patient during a periodontal examination.