The horizontal plate of palatine bone is a quadrilateral part of the

palatine bone In anatomy, the palatine bones () are two irregular bones of the facial skeleton in many animal species, located above the uvula in the throat. Together with the maxillae, they comprise the hard palate. (''Palate'' is derived from the Latin ''pal ...

, and has two surfaces and four borders.

Surfaces

The superior surface, concave from side to side, forms the back part of the floor of the

nasal cavity The nasal cavity is a large, air-filled space above and behind the nose in the middle of the face. The nasal septum divides the cavity into two cavities, also known as fossae. Each cavity is the continuation of one of the two nostrils. The nasal c ...

. The inferior surface, slightly

concave Concave or concavity may refer to: Science and technology * Concave lens * Concave mirror Mathematics * Concave function, the negative of a convex function * Concave polygon A simple polygon that is not convex is called concave, non-convex or ...

and rough, forms, with the corresponding surface of the opposite bone, the posterior fourth of the

hard palate The hard palate is a thin horizontal bony plate made up of two bones of the facial skeleton, located in the roof of the mouth. The bones are the palatine process of the maxilla and the horizontal plate of palatine bone. The hard palate spans ...

. Near its posterior margin may be seen a more or less marked transverse ridge for the attachment of part of the

aponeurosis An aponeurosis (; plural: ''aponeuroses'') is a type or a variant of the deep fascia, in the form of a sheet of pearly-white fibrous tissue that attaches sheet-like muscles needing a wide area of attachment. Their primary function is to join muscl ...

of the

tensor veli palatini The tensor veli palatini muscle (tensor palati or tensor muscle of the velum palatinum) is a broad, thin, ribbon-like muscle in the head that tenses the soft palate. Structure The tensor veli palatini is found anterior-lateral to the levator ve ...

Borders

The anterior border is serrated. It articulates with the palatine process of maxilla. The posterior border is concave, free, and serves for the attachment of the

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. T ...

. Its medial end is sharp and pointed, and, when united with that of the opposite bone, forms a projecting process, the

posterior nasal spine The posterior nasal spine is part of the horizontal plate of the palatine bone of the skull. It is found at the medial end of its posterior border. It is paired with the corresponding palatine bone to form a solid spine. It is the attachment of th ...

for the attachment of the

musculus uvulae The palatine uvula, usually referred to as simply the uvula, is a conic projection from the back edge of the middle of the soft palate, composed of connective tissue containing a number of racemose glands, and some muscular fibers. It also conta ...

. The lateral border is united with the lower margin of the perpendicular plate, and is grooved by the lower end of the

greater palatine canal The greater palatine canal (or pterygopalatine canal) is a passage in the skull that transmits the descending palatine artery, vein, and greater and lesser palatine nerves between the pterygopalatine fossa and the oral cavity. Structure The gre ...

. The medial border, the thickest, is serrated for articulation with its fellow of the opposite side; its superior edge is raised into a ridge, which, united with the ridge of the opposite bone, forms the nasal crest for articulation with the posterior part of the lower edge of the

vomer The vomer (; lat, vomer, lit=ploughshare) is one of the unpaired facial bones of the skull. It is located in the midsagittal line, and articulates with the sphenoid, the ethmoid, the left and right palatine bones, and the left and right maxil ...

Additional images

File:Gray187.png, Base of skull. Inferior surface. File:Gray196.png, Roof, floor, and lateral wall of left nasal cavity. File:Gray996.png, Permanent teeth of upper dental arch, seen from below. File:Horizontal plate.jpg, Horizontal plate

References

External links

{{Authority control Bones of the head and neck