Periodontal probe for measuring overjet and overbite
With the periodontal probe, both an overjet and an overbite can be measured. The scale on the probe shows the size of the overjet or overbite. The probe shows a line per millimeter (the first line is 2 mm) and after every 5 mm there is a thicker line (which is one millimeter wide by itself). This way you can quickly see the number of millimeters of the overjet or overbite.
There are different tools for measuring an overjet and overbite, depending on what needs to be measured.
• To measure an overjet (also called: sagittal or horizontal overbite), the periodontal probe, a ruler and the SOB measurer can be used.
• To measure an overbite (also: vertical overbite), the periodontal probe or a ruler can be used. This can be a negative overbite (which measures the space between the lower and upper incisors at rest; also called open bite) and a positive overbite (which measures the extent to which the upper incisors are placed over the lower incisors at rest). The positive overbite can be measured by first making a horizontal line with a pencil, directly below the incisal edge of the upper central incisors (this line will then appear on the labial side of the lower central incisors). Then measure the distance from the incisal edge of the lower central incisors to the set mark.
• Measuring an overjet in combination with an open bite (a negative overbite) is only possible with an SOB measurer.