FOR LOWER ARCH- (original equation tooth measurement from left side of the arch, revised
equation- derived from measurements taken from teeth from both sides of the arch)
1. Form the cast measure the MD width of lower incisors
2. From the Periapical radiograph measure the MD width of the 4 and 5
3. Total the MD width of 4 incisors and compare it to the chart
4. Repeat step 1 & 3 for other side of the arch (in Staley Kerber analysis part)
Measured values Estimated value
23 mm 18.4 mm
24 mm 19.0 mm
25 mm 19.7 mm
26 mm 220.3 mm
27 mm 21 mm
28 mm 21.6 mm
29 mm 22.3 mm
30 mm 22.9 mm