A mechanism for closure of the secondary palate

Publisher Website
Google Scholar
Abstract
Before the palate begins to close in mouse and rat embryos the cranial base in flexed in the area of the craniopharyngeal canal. As the process of palate closure progresses there is a gradual reduction in the flexure of the cranial base until finally, when the palatine processes are horizontal, the cranial base is almost straight. Rapid growth and straightening of the cranial base might play a role in palate closure by providing the “internal shelf force.” This hypothesis can be demonstrated by means of a mechanical model. The model consists of a thin sheet of plastic cut in the shape of a sagittal view of a vertical shelf and a piece of string attached to the convex border of the model shelf to represent the cranial base (in its flexed position). When the string is pulled, and the angulation of the “cranial base” is reduced to a straight line, the distal part of the model palatine process rotates to a position perpendicular to the proximal or attached part of the shelf, in a manner similar to that of the palatine processes in the embryo.