Palatine bone

The palatine bone (os palatinum) is paired, participates in the formation of the hard palate, the orbit, the pterygoid palatine fossa. In it, two plates are distinguished - horizontal and vertical, connecting at almost a right angle, and three processes.

The horizontal plate (lamina honsontalis) is mediated with the same edge of the same plate of the palatine bone of the opposite side. The posterior edge of the horizontal plate is free, a soft palate is attached to it. The anterior edge of the plate is connected to the posterior margin of the palatine process of the upper jaw. As a result, the palatine processes and horizontal plates of the palatine bones form a solid skeleton on the whole skull (palatum osseum).

The perpendicular plate (lamina perpendicularis) participates in the formation of the lateral wall of the nasal cavity. On the lateral surface of this plate is located a large palatal sulcus (sulcus palatinus major). It, together with the same grooves of the upper jaw and pterygoid process of the sphenoid bone, forms a large palatine canal (canalis palatinus major). On the medial surface of the perpendicular plate there are two horizontal ridges. The upper crista ridge (crista ethmoidalis) serves to attach the middle nasal shell, and the lower shell crista (crista conchalis) - the lower nasal shell.

The palatine bone has an orbital, wedge-shaped and pyramidal processes.

The processus orbitalis (processus orbitalis) is directed forward and lateral, participates in the formation of the orbital wall of the orbit.

The sphenoid processus (processus sphenoidalis) is oriented backward and medially. It connects to the lower surface of the body of the sphenoid bone. The glaucous and wedge-shaped processes limit the wedge-palatine incision (incisura sphenopalatine), which together with the sphenoid bone body limits the wedge-palatal opening.

The pyramidal processus (processus pyramidalis) comes from the palatine bone down, laterally and backward. Through this process pass narrow small palatine canals (canales palatini minores) opening with holes on the palatal surface of the pyramidal process.

The maxillary, or maxillary sinus (sinus maxillaris) is the cavity of the upper jaw. The anterior wall of the sinus in the center is thin, thickens in the peripheral parts. This wall is formed by a part of the upper jaw between the infraorbital margin and the alveolar process. The zadnelateralnaya wall corresponds to the bucca of the upper jaw. To the anterior section of the medial wall of the maxillary sinus is a nasolacrimal canal, to the posterior part - lattice cells. The lower wall of the sinus forms the alveolar process of the upper jaw. The upper wall of the sinus is also the bottom wall of the orbit. The maxillary sinus opens into the middle nasal passage. The sinus changes in shape and size.

The frontal sinus (sinus frontalis) varies considerably in size. The septum, dividing the frontal sinus into the right and left parts, is usually asymmetric. The frontal sinus communicates with the middle nasal passage.

The sphenoid sinus (sinus sphenoidalis) is located in the body of the sphenoid bone. The lower wall of the sinus is involved in the formation of the wall of the nasal cavity. To the upper part of the lateral wall is a cavernous sinus. The sphenoid sinus is usually subdivided into two asymmetric parts by a sagittal septum. Sometimes the septum is absent. The sphenoid sinus communicates with the superior nasal passage.

The airway cavities communicating with the nasal cavity are the front, middle and posterior cells of the latticed bone.

Bony palate (palatum osseum) is formed by the median line connected by the palatine processes of the right and left upper jaws, as well as by the horizontal plates of the palatine bones. It serves as a solid (bone) base of the upper wall of the oral cavity. Front and sides of the skull are limited by the alveolar processes of the upper jaws, forming the upper alveolar arch. On the midline of the bone, the palate passes the median palatine suture (sutura palatina mediana). At the anterior end of the sky is the incisive canal (canalis incisivus) for the eponymous nerve. The transverse palatine suture (sutura palatina transversa) is connected with the posterior edge of the palatine processes of the upper jaws with horizontal plates of the palatine bones. In the lateral sections of this suture, at the base of each horizontal plate, there is an opening of the large palatal canal and 2-3 small palatine orifices, through which the oral cavity communicates with the pterygopalatine fossa.

The upper and lower alveolar arches together with the teeth, as well as the body and branches of the lower jaw form the skeleton of the anterior and lateral walls of the oral cavity.

Behind the upper jaw there is a fossa infratemporalis (fossa infratemporalis), which is delimited from the temporal fossa by the dorsal crest of the large wing of the sphenoid bone. The upper wall of the inframammary fossa is formed by the temporal bone and the large wing of the sphenoid bone (trailing crest). The medial wall is formed by the lateral plate of the pterygoid process of the sphenoid bone. The anterior wall of this fossa is the upper jawbone and the malar bone. On the lateral side, the pterygoal fossa is partly covered by the branch of the lower jaw. At the front, the tracheal fossa is communicating through the lower orbital fissure with the orbit, and medially through the pterygoid-maxillary fissure (flssшra pterygomaxillaris) - with the pterygoid palatine fossa.

The pterygo-palatine fossa pterygopalatina has 4 walls: anterior, anterior, posterior and medial. The anterior wall of the fossa is the tubercle of the upper jaw, the upper is the lateral surface of the body and the base of the large wing of the sphenoid bone, the posterior is the base of the pterygoid process of the sphenoid bone, the medial is the perpendicular plate of the palatine bone. From the lateral side, the pterygopalatine fossa is associated with the pteryphalic fossa. The pterygo-palatine fossa narrows gradually to the large palatine canal (canalis palatinus major), which below the upper jaw (lateral) and the palatine bone (medially). In the pterygoid palatine, 5 holes are opened. Medially, this fossa communicates with the nasal cavity through the wedge-palatine orifice, from above and backwards - with the middle cranial fossa by means of a round hole, posteriorly with the area of the lacerated hole by the pterygoid canal, downwards - with the oral cavity through the large palatal canal.

With the eye socket, the pterygoid-palatine fossa is reported through the lower orbital fissure.

Bony palate (palatum osseum) is formed by the median line connected by the palatine processes of the right and left upper jaws, as well as by the horizontal plates of the palatine bones. It serves as a solid (bone) base of the upper wall of the oral cavity. Front and sides of the skull are limited by the alveolar processes of the upper jaws, forming the upper alveolar arch. On the midline of the bone, the palate passes the median palatine suture (sutura palatina mediana). At the anterior end of the sky is the incisive canal (canalis incisivus) for the eponymous nerve. The transverse palatine suture (sutura palatina transversa) is connected with the posterior edge of the palatine processes of the upper jaws with horizontal plates of the palatine bones. In the lateral sections of this suture, at the base of each horizontal plate, there is an opening of the large palatal canal and 2-3 small palatine orifices, through which the oral cavity communicates with the pterygopalatine fossa.

The upper and lower alveolar arches together with the teeth, as well as the body and branches of the lower jaw form the skeleton of the anterior and lateral walls of the oral cavity.