Sagittal Growth of the Nasomaxillary Complex during the Second Trimester of Human Prenatal Development

¹ Department of Anatomy, University of Michigan, Ann Arbor, Michigan

Changes in size, shape, and proportion of the nasomaxillary region have been studied in human fetuses representing the fourth through the sixth month of development. For this a series of linear and angular measurements of the cranial base, nasal septum, and palatal regions have been made. The data were related to crown-rump length and subjected to group statistical analyses to demonstrate growth trends of the upper face.

The findings suggested that several distinct patterns of nasomaxillary growth may exist during the period studied. First, angular relationships between contiguous areas of the nasomaxillary region showed no significant changes with increasing crown-rump length. Second, linear measurements of the cranial base, nasal septum, and palate were correlated with increases in crown-rump length. Third, the directional growth pattern of the upper face exhibited a downward and forward growth away from the anterior cranial base and the landmark sella.