Perpendicular plate

The perpendicular plate of the palatine bone is the vertical and lateral portion of the palatine bone. It contributes to the lateral delimitation of the opening of the nasal cavity or choanae. It is continuous ventrally with the horizontal plate of the palatine bone.

The perpendicular plate of the palatine bone is flattened laterally and has two faces: the nasal face and the maxillary face.

The perpendicular plate of the palatine bone is connected to:

• the pterygoid process of the basisphenoid bone caudally,

• the maxilla, ethmoid bone and vomer rostrally,

• the frontal bone and presphenoid bone, dorsally.

Its middle part, smooth and excavated, forms the pterygopalatine fossa (Fossa pterygopalatina) and is carved out by a cavity: the sphenoidal sinus.