Can 2 mm reduction of nasal sill result in a 3-4 mm reduction in nose widening when smiling?

The nasal sill Is the part of the nostril where it curves towards the footplate of the medial crus. If 2 mm is removed from each side, that would result in 4 mm of narrowing of the nasal base. Even with smiling. I hope this helps! Sincerely, Dr Joseph

Skin is elastic and stretches. Especially when smiling, the skin along the nose and ala moves. A 2 mm nasal sill incision will create less than 3-4 mm of width reduction.

It is unlikely that a 2mm reduction in the sill area will reduce the smiling width of the nose by 3-4mm. However, the appearance of the narrowing is subjective and could be perceived as more than 2mm. The exact changes in the size with smiling depend also on the nasal flare that happens with nasalis muscle.
Regards
Dr. J