Which star-marked tooth number is the largest?

Which star-marked tooth number is the largest?

• A. 31
• B. 28
• C. 20
• D. 18

Answer: (A)

In this numbering system, two digits identify a tooth: the first digit is the quadrant, and the second digit is the tooth’s position from the midline to the back. To find the largest among the given codes, compare them as two-digit numbers—the one with the greater value is the largest. Among the options, the one located in the lower-left quadrant toward the front (the central incisor position) has the highest numeric value. The other codes belong to quadrants with smaller tens digits or have smaller ones digits, so they’re considered smaller in this numeric sense. So the star-marked tooth in the lower-left quadrant central incisor position is the largest.

In this numbering system, two digits identify a tooth: the first digit is the quadrant, and the second digit is the tooth’s position from the midline to the back. To find the largest among the given codes, compare them as two-digit numbers—the one with the greater value is the largest.

Among the options, the one located in the lower-left quadrant toward the front (the central incisor position) has the highest numeric value. The other codes belong to quadrants with smaller tens digits or have smaller ones digits, so they’re considered smaller in this numeric sense.

So the star-marked tooth in the lower-left quadrant central incisor position is the largest.