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

INTRODUCTION

This study aimed to investigate sex differences in age-related changes to the dentoskeletal and soft tissue profile between 12-62 years of age using a superimposition-based cephalometric method.

METHODS

A total of 60 subjects (27 males and 33 females) were followed longitudinally. Lateral cephalograms were obtained at ages 12 (T1), 15 (T2), 30 (T3), and 62 (T4). Of note, 46 angular and linear cephalometric variables were measured using a cranial base-registered superimposition method that corrected for age-related displacement of the Nasion and Sella landmarks. Sex differences in changes between time points were analyzed using independent-samples t tests.

RESULTS

During adolescence (12-15 years of age), males exhibited greater sagittal advancement of the maxilla and mandible, as well as larger increases in facial height and jaw dimensions compared with females. Between 15-30 years, sexual dimorphism peaked: males showed anterior mandibular rotation accompanied by increased mandibular protrusion, whereas females exhibited mandibular incisor proclination and reductions in the nasolabial angle and lip protrusion. After the age of 30 years, maturational trajectories converged, with both sexes showing posterior mandibular rotation and retroclination, retursion of maxillary and mandibular incisors, and similar soft-tissue changes.

CONCLUSIONS

Sex-specific growth patterns are most pronounced during adolescence and young adulthood but diminish after the third decade. Soft tissue profile changes tend to occur earlier in females. The age-related reduction in incisor and lip prominence, particularly among females, should be taken into consideration when planning orthodontic, prosthodontic, and orthognathic treatments.