Prenatal growth pattern of the human maxilla

Area of Science:

• Craniofacial development
• Maxillofacial morphogenesis
• Embryonic skeletal development

Background:

• Maxillary structure growth has been a long-standing debate in maxillofacial morphogenesis.
• Understanding early maxilla development is crucial for comprehending craniofacial anomalies.

Purpose of the Study:

• To identify and characterize primary growth centers in the developing human maxilla.
• To formulate a model, the maxillary trapezoid (MT), based on these growth centers.
• To analyze the dimensional changes and growth patterns of the fetal maxilla.

Main Methods:

• Analysis of 120 normal fetal maxillae (16–41 weeks gestation).
• Utilized palatal radiograms and frontal histologic sections.
• Radiologic imaging and histological examination to identify growth centers and formulate the MT.

Main Results:

• Identified two pairs of accentuated growth areas, termed primary growth centers, forming the maxillary trapezoid (MT).
• Documented and statistically analyzed the dimensional increase of the MT during fetal development.
• Primary growth centers are most active until 20 weeks gestation; thereafter, peripheral intramembranous bone formation enhances maxilla growth.

Conclusions:

• The identified growth centers demarcating the MT are fundamental structures in human maxilla development.
• Early fetal maxilla growth is driven by these central primary growth centers.
• Later fetal maxilla growth involves peripheral intramembranous ossification, complementing the maturation of central growth areas.