Sex differences in dentoskeletal and soft tissue profile changes: A 50-year longitudinal study

Area of Science:

• Orthodontics
• Craniofacial Biology
• Growth and Development

Background:

• Investigating sex differences in age-related dentoskeletal and soft tissue profile changes.
• Utilizing a superimposition-based cephalometric method for accurate analysis.

Purpose of the Study:

• To analyze sex-specific differences in craniofacial growth from adolescence to older adulthood.
• To identify age periods where sexual dimorphism in facial development is most pronounced.
• To inform clinical treatment planning based on observed sex-specific changes.

Main Methods:

• Longitudinal study of 60 subjects (27 males, 33 females) from age 12 to 62.
• Collection of lateral cephalograms at ages 12, 15, 30, and 62.
• Measurement of 46 cephalometric variables using cranial base-registered superimposition.

Main Results:

• Males showed greater sagittal advancement and jaw dimension increases during adolescence (12-15 years).
• Sexual dimorphism peaked between 15-30 years with distinct male and female changes (e.g., mandibular rotation, incisor proclination).
• Post-30 years, growth trajectories converged with similar posterior rotation and incisor retroclination in both sexes.

Conclusions:

• Sex-specific growth patterns are most evident during adolescence and young adulthood, decreasing significantly after age 30.
• Females tend to exhibit soft tissue profile changes earlier than males.
• Clinical considerations for orthodontic, prosthodontic, and orthognathic treatments should account for age-related reductions in incisor and lip prominence, especially in females.