Which landmark pair is used to calculate the facial index?

Which landmark pair is used to calculate the facial index?

• A. Of- Gn and Au- Au
• B. N- Gn and Go- Go
• C. Of- Pg and Au- Au
• D. N- Gn and Zy- Zy

Answer: (D)

The facial index measures how tall the face is compared to how wide it is. To get those dimensions, you use the vertical height from Nasion to Gnathion (N-Gn) for the facial height, and the horizontal width across the cheeks between the Zygaions on each side (Zy-Zy) for the facial width. The index is calculated as (N-Gn) divided by (Zy-Zy) times 100. This combination directly captures the standard height-to-width relationship of the face, so using N-Gn for height and Zy-Zy for width is the correct approach. Other landmark pairs don’t reflect the conventional width measurement or the standard vertical height needed for this index.

The facial index measures how tall the face is compared to how wide it is. To get those dimensions, you use the vertical height from Nasion to Gnathion (N-Gn) for the facial height, and the horizontal width across the cheeks between the Zygaions on each side (Zy-Zy) for the facial width. The index is calculated as (N-Gn) divided by (Zy-Zy) times 100. This combination directly captures the standard height-to-width relationship of the face, so using N-Gn for height and Zy-Zy for width is the correct approach. Other landmark pairs don’t reflect the conventional width measurement or the standard vertical height needed for this index.