Male postpubertal facial growth in Class II malocclusions

Area of Science:

• Orthodontics and Dentofacial Orthopedics
• Craniofacial Growth and Development

Background:

• Postpubertal facial growth is crucial for understanding orthodontic treatment outcomes.
• Class II malocclusion presents specific challenges in craniofacial development.
• Limited data exists on the extent of maxillary and mandibular growth in late adolescence for Class II individuals.

Purpose of the Study:

• To quantify maxillary and mandibular growth changes in male subjects with Class II skeletal characteristics from age 16 to 20.
• To compare the magnitude of mandibular growth relative to maxillary growth during this period.
• To analyze changes in mandibular rotation and facial height proportions.

Main Methods:

• Lateral cephalograms were analyzed for 39 untreated male subjects with Class II characteristics.
• Measurements were taken at two time points: age 16 and age 20.
• Key cephalometric variables assessed included maxillary and mandibular lengths, mandibular plane angle, and anterior/posterior face heights.

Main Results:

• Significant increases in mean maxillary and mandibular measurements were observed between ages 16 and 20.
• Mandibular growth (Co-Gn) was approximately three times greater than maxillary growth (Co-A), averaging 4.3 mm.
• The mandible exhibited a mean anterior superior rotation (1.47° reduction in mandibular plane angle) with greater posterior than anterior face height increase; incisor angulation remained stable.

Conclusions:

• Substantial postpubertal maxillary and mandibular growth occurs in Class II males between ages 16 and 20.
• The mandible demonstrates significant growth and a tendency towards anterior superior rotation during late adolescence.
• Observed growth patterns in this Class II sample are comparable to those reported for Class I individuals, suggesting similar late adolescent developmental trajectories.