Final answer:
A periodontal probe is used to measure the depth of periodontal pockets, much like a ruler with millimeter markings measures small objects.
Step-by-step explanation:
A periodontal probe is an instrument calibrated in millimeters that is used to locate and measure the depth of periodontal pockets. When considering what tool to use for precise measurements, it's essential to match the tool with the unit appropriate for the object's size. A periodontal probe is specifically designed for dental use, allowing dentists or hygienists to determine the health of a patient's gums by measuring the depth of the spaces between the teeth and gums.
Much like measuring small objects such as a toothpick with a ruler marked with millimeters for precision, the periodontal probe provides accurate measurements necessary for dental health assessments. This probe can be compared to the precision offered by a scanning probe microscope or a scanning electron microscope (SEM), which can observe minute details at a microscopic level.