periodontal probe [Gk, peri, around, odous, tooth; L, probare, to test] , 1. a slender, tapered, flat or cylindric instrument with indentations spaced in millimeters, designed for introduction into the gingival sulcus for the purpose of measuring its depth. 2. a slender tapered instrument with or without millimeter indentations or contrasting colors for measuring furcations of the roots of premolars and molars. Also called furcation probe.
