What tooth number is the star on?

What tooth number is the star on?

• A. 18
• B. 3
• C. 9
• D. 21

Answer: (D)

The star is placed on a specific tooth using the universal numbering system, which assigns numbers 1 through 32 to adult teeth. In this system, the lower left quadrant numbers run from the midline toward the back: central incisor is the last in that quadrant, followed by the lateral incisor, canine, first premolar, second premolar, first molar, second molar, and finally the third molar at the back. If the star is on the first premolar in the lower left quadrant, that tooth corresponds to twenty-one. So the star marks the lower left first premolar, tooth number twenty-one.

The star is placed on a specific tooth using the universal numbering system, which assigns numbers 1 through 32 to adult teeth. In this system, the lower left quadrant numbers run from the midline toward the back: central incisor is the last in that quadrant, followed by the lateral incisor, canine, first premolar, second premolar, first molar, second molar, and finally the third molar at the back. If the star is on the first premolar in the lower left quadrant, that tooth corresponds to twenty-one. So the star marks the lower left first premolar, tooth number twenty-one.