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→Temporal Bone (os temporale)
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==== Frontal Bone (''os frontale'') ====
The frontal bone is a paired structure joined by the '''interfrontal suture''' between the cranium and the face and enclosing the '''frontal sinuses'''. The nasal and lacrimal bones border the frontal squama section and form the zygomatic process laterally and part of the orbit dorsally. Lacrimal glands are also present near the orbit. The '''temporal line''' extends into the '''external sagittal crest'''. Ruminants also have a '''cornual process''' in [[Horn - Anatomy & Physiology|horned]] variants. The nasal section is the rostral part of the frontal bone and the orbital part is perforated by the '''ethmoidal foramen'''. Medially the '''dorsal oblique muscle''' of the eyeball attaches. The temporal part provides the muscle attachments for the '''temporalis muscle'''. <br> <br>
==== Parietal Bone (''os parietale'') ====
[[Image:Pareital Bone.jpg|thumb|right|150px|'''Parietal Bone''', nabrown, 2008]] The parietal bone is a paired structure and forms the dorsolateral wall of the cranium with the cccipital bone caudally and the frontal bone rostrally. It is composed of a parietal plane, temporal plane and a nuchal plane (in the ox). Internally the grooves and ridges correspond with the gyri and sulci of the brain. There is also an '''interparietal bone''' between the occipital bone and the parietal bone which fuses with age. <br> <br> <br> <br>>
==== Ethmoid Bone (''os ethmoidale'') ====
[[Image:Nasal Cavities.jpg|thumb|right|150px|'''Nasal Cavities''', David Bainbridge]] The ethmoid bone forms part of the cranial and facial parts of the skull and is located deep in the orbit. External lamina consist of the roof plate, floor plate and paired orbital plates. The ethmoid bone is separated from the cranial cavity by the '''cribiform plate'''. Numerous small foramina exist where the '''olfactory nerve''' ([[Cranial Nerves - Anatomy & Physiology|CN I]]) passes through. The perpendicular plate splits the ethmoid into two halves and the ethmoid larbyrinth protrudes from the ethmoid tubes. The tubes are composed of two rows of '''ethmoturbinates''' and air filled '''ethmoidal meatuses'''. Secondary ethmoturbinates may also be present. Ethmoturbinates are divided into '''endoturbinates''' and '''ectoturbinates'''. The first endoturbinate forms the dorsal nasal conchae and the second endoturbinate froms the middle nasal conchae. The endoturbinates form 3 nasal meatuses; the '''dorsal nasal meatus''', the '''middle nasal meatus''' and the '''ventral nasal meatus'''. [[Image:Ethmoid Turbinates.jpg|thumb|right|150px| '''Ethmoid Turbinates''', nabrown, 2008]]<br> <br>
==== Nasal Bone (''os nasale'') ====
The nasal bone is a paired structure and forms the roof of the nasal cavity. '''Dorsal nasal conchae''' attach to the '''ethmoidal crest''' on the internal surface. A rostral suture forms the apex and between the nasal and incisive bones is the '''nasoincisive notch'''. <br> <br>
==== Lacrimal Bone (''os lacrimale'') ====
The lacrimal bone forms part of the lateral wall of the face and orbit and is situated near the '''medial canthus'''. It articulates with the '''frontal bone, zygomatic bone''' and '''maxilla'''. It also articulates with the '''nasal bone''' in ruminants and the horse and articulates with the '''palatine bone''' in carnivores. It is composed of an orbital and facial part separated by supra- and infraorbital margins. The '''nasolacrimal duct''' is present by the margin of the orbital surface. The '''ventral oblique muscle''' attaches caudal to the margin of the orbital surface. The nasal surface forms the boundaries of the '''maxillary and frontal sinuses'''. <br> <br>
==== Zygomatic Bone (''os zygomaticum'') ====
The zygomatic bone is lateral and ventral to the lacrimal bone and forms the orbit and zygomatic arch. The supraorbital margin is formed by the zygomatic process of the temporal bone and the frontal process of the zygomatic bone. The facial crest is present on lateral surface. <br> <br>
==== Incisive Bone (''os incisivium'') ====
[[Image:Cow skull lateral view.jpg|thumb|right|150px|'''Cow skull lateral view''', nabrown, 2008]] The incisive bone is a paired structure composed of body, nasal, palatine and alveolar parts. It joins with the maxilla to form the '''interalveolar margin'''. It also forms the rostral part of the facial section of the skull, the roof of the '''[[Hard Palate|hard palate]]''' and the opening to the nasal cavity. The alveolar process forms conical sockets for the incisor teeth. <br> <br> <br> <br> <br>
==== Palatine Bone (''os palatinum'') ====
[[Image:Palatine Bone.jpg|thumb|right|150px|'''Palatine Bone''', nabrown, 2008]] The palatine bone is a paired structure between the maxilla, sphenoid and pterygoid bones. It is composed of a horizontal plate (forms part of the [[Hard Palate|hard palate]]), perpendicular plate (forms the dorsal and lateral walls of the nasopharyngeal meatus) and the choanae. The '''nasal crest''' present on the horizontal plate. The '''palatine sinus''' is present on horizontal plate. <br> <br>
==== Vomer ====
The vomer is unpaired and extends from the choanae of the palatine bone to the floor of the nasal cavity. It attaches to the median nuchal crest and has a '''septal sulcus''' which surrounds nasal cavity. <br> <br>
==== Pterygoid Bone (''os pterygoideum'') ====
The pterygoid bone is a paired structure bordered by the '''palatine''' and '''sphenoid bones'''. It forms the dorsal and lateral walls of the '''nasopharyngeal cavity'''. The '''pterygoid hamulus''' is formed by the pterygoid bone. <br> <br>
==== Maxilla ====
The maxilla forms most of the facial part of the skull, including the lateral walls of the face, nasal cavity, [[Oral Cavity Overview - Anatomy & Physiology|oral cavity]] and [[Hard Palate|hard palate]]. It also forms the ventral nasal conchae and articulates with all of the facial bones as it is the largest bone of the face. The maxillary body encloses the '''maxillary sinuses''' and forms the external surface of the face. It also forms the '''facial crest'''. The '''infraorbital foramen''' is palpable. The '''conchal crest''' is on nasal surface where the ventral nasal conchae attaches. The '''lacrimal canal''' opens into the '''lacrimal foramen''' on the nasal surface. The '''pterygopalatine surfaces''' are the caudal part of the maxilla which terminate in the '''maxillary tubercle''' where the '''sphenopalatine, maxillary''' and '''caudal palatine foramen''' are present. The '''alveolar processes''' present are separated by '''interalveolar septa'''. The '''palatine process''' forms the '''[[Hard Palate|hard palate]]''' with the palatine bone. The '''palatine fissure''' is formed at the articulation with the incisive bone. The nasal surface of palatine process forms the '''nasal crest''' and encloses part of the palatine sinuses. The oral surface has numerous palatine foramina present. <br> <br>
==== Mandible (''mandibula'') ====
The mandible can be divided into the '''body''' and the '''ramus'''. The body of the mandible supports the incisor teeth (rostrally) and cheek teeth (caudally). The section of the body which does not support any teeth is called the '''interalveolar margin''' or '''diastema'''. The mandibule also contains the '''mandibular canal''' and the '''mental foramen'''. The '''facial notch''' is on the ventral surface where the '''parotid duct''' (in herbivores) and facial vessels run. The '''ramus''' extends from the caudal end of the body dorsally towards the zygomatic arch. The '''masseter muscle''' attaches to the lateral surface at the '''masseteric fossa'''. The '''medial pterygoid''' attaches to the medial surface at the '''pterygoid fossa'''. The angle of the mandible terminates dorsally in the '''condylar process''' and the '''coronoid process''' which are separated by the '''mandibular notch'''. The '''temporal muscle''' inserts onto the '''coronoid head'''. The condylar process articulates with the mandibular process of the skull (see [[Mastication#Jaw_Articulation|here]]). <br> <br> <br> <br> <br> <br> <br> <br> <br> <br> <br> <br>
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