6,273
edits
Changes
Jump to navigation
Jump to search
→Sphenoid Bone (os sphenoidale)
==== Sphenoid Bone (''os sphenoidale'') ====
==== Sphenoid Bone (''os sphenoidale'') ====
The sphenoid bone forms the base of the neurocranium and is composed of a body and wings. The bones are separated by cartilage which ossifies with age. The '''presphenoid (''os praespenoidale'')''' is rostral and has a caudal fossa which is a hollow body with sphenoid sinuses located inside. Within the sinuses are the '''optic chiasma''' and '''optic canal'''. The '''basisphenoid (''os basispenoidalis'')''' is caudal and has a '''median cranial fossa'''. The wings oppose the temporal bone, maxilla, orbit and the brain. The wings also form the '''oval foramen'''. The pterygoid processes are also present.
The sphenoid bone forms the base of the neurocranium and is composed of a body and wings. The bones are separated by cartilage which ossifies with age. The '''presphenoid (''os praespenoidale'')''' is rostral and has a caudal fossa which is a hollow body with sphenoid sinuses located inside. Within the sinuses are the '''optic chiasma''' and '''optic canal'''. The '''basisphenoid (''os basispenoidalis'')''' is caudal and has a '''median cranial fossa'''. The wings oppose the temporal bone, maxilla, orbit and the brain. The wings also form the '''oval foramen'''. The pterygoid processes are also present.
<br />
<br />
==== Temporal Bone (''os temporale'') ====
[[Image:Zygomatic arch.jpg|thumb|right|200px|'''Canine Zygomatic Arch''', nabrown, 2008]] The temporal bone is composed of '''squamous, petrosal''' and '''tympanic''' parts and forms the lateral wall of the cranial cavity. It articulates with the frontal, parietal and sphenoid bones. The squamous element joins the temporal process of the zygomatic bone to form the '''zygomatic arch''' and forms the articulating surface of the '''[[Mastication#Jaw_Articulation|temporomandibular joint]]'''. An '''articular tubercle''' and '''mandibular fossa''' are present. Occipital process and retrotympanic processes surround the '''external acoustic meatus''' whilst the petrosal part encloses the inner ear internally via the '''internal acoustic meatus'''. Ventrally this structure forms the '''mastoid process'''. The '''styloid process''' attaches the '''[[Hyoid Apparatus - Anatomy & Physiology|hyoid apparatus]]''' and a '''stylomastoid foramen''' is also present. The tympanic part is the ventral section of the temporal bone containing the '''tympanic bulla'''. The '''tympanic membrane''' separates tympanic cavity from '''external acoustic meatus''' and encloses the '''auditory ossicle''' dorsally. The musculotubal canal contains tensors of the [[Soft Palate#Musculature_and_Innervation|soft palate]].
<br />
<br />
<br />
<br />