Related Experiment Video
Updated: May 15, 2026

Midface Hypoplasia and Cranial Base Morphology in Syndromic Craniosynostosis: A Comparative Analysis Study Using a Predictive Regression Model
Published on: November 4, 2025
Facial asymmetry index in normal young adults
1Faculty of Dentistry, Craniofacial Research Center, Chang Gung Memorial Hospital, Taipei, Taiwan. sshuang@ms1.hinet.net
Objectives:
To differentiate a symmetric face from an asymmetric face by analyzing a three-dimensional (3D) facial image and plotting the asymmetry index (AI) on a facial symmetry diagram.
Setting And Sample Population:
Sixty healthy Chinese adults (30 men and 30 women, mean age: 27.7 + 4.9 years old) without any craniofacial deformity were recruited on a voluntary basis from a medical center.
Material And Methods:
A 3D facial image of each participant was captured by a GENEX 3D FACE CAM system. Sixteen facial landmarks, as defined by Farkas, were selected on each 3D facial image. The AI was calculated for each landmark.
Results:
The norm for the AI varied from 0.76 to 2.82. The landmarks located on the upper face had a smaller AI than the landmarks located on the lower face. A facial symmetry diagram was designed according to the mean, one standard deviation, and 2 standard deviations of AI for each landmark.
Conclusions:
The 3D facial asymmetry can be documented with AI. The landmarks located on the upper face had a smaller AI than the landmarks located on the lower face. The facial symmetry diagram can identify efficiently the location of asymmetry on a face.
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