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Updated: Jun 14, 2026
09:26
Quantification of Orofacial Phenotypes in Xenopus
Published on: November 6, 2014
Lower face asymmetry as a marker for developmental instability
Philippe P Hujoel1, Erin E Masterson1, A-M Bollen2
1Oral Health Sciences, School of Dentistry, University of Washington, Box 357475, Seattle, WA, 98115.
Summary
Lower face asymmetries affect one in four adolescents, with distinct patterns linked to environmental factors and developmental origins of health. These asymmetries may indicate early developmental stress.
Area of Science:
- Human anatomy and developmental biology
- Public health and epidemiology
- Genetics and environmental influences on development
Background:
- Craniofacial fluctuating asymmetries are linked to mortality from degenerative diseases.
- Understanding lower face asymmetries may offer insights into developmental origins of health and disease (DOHaD).
Purpose of the Study:
- To investigate if lower face asymmetries in adolescents serve as a marker for DOHaD.
- To determine the prevalence and characteristics of lower face asymmetries in a US adolescent population.
Main Methods:
- Analysis of lower face asymmetry in 6654 US adolescents (ages 12-17) from the National Health Examination Survey III (1966-1970).
- Classification of asymmetry based on unilateral prognathic (forward) or retrognathic (backward) mandibular occlusion.
- Investigation of directional versus fluctuating asymmetry and associations with race/ethnicity, handedness, and household size.
Main Results:
- Lower face asymmetries were present in 25% of US adolescents.
- Unilateral retrognathic occlusions (17.0%) were fluctuating asymmetries associated with race/ethnicity.
- Unilateral prognathic occlusions (7.6%) were directional asymmetries linked to larger household size and handedness.
Conclusions:
- Lower face asymmetries are associated with race/ethnicity, handedness, and environmental factors like household size.
- These asymmetries may serve as indicators of environmental stress and cerebral lateralization during early development.
- Findings contribute to understanding DOHaD through craniofacial morphological markers.
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