Bones and cavities of the facial cranium TMJ
Bones and cavities of the facial cranium
TMJ
Anterior Skull frontal bone supraorbit al foramen zygomatic bone mandibula r symphysis mental foramen glabella infraorbita l foramen maxillar y bone alveolar fossa mandible
Anterior Skull perpendicular plate superior orbital fissure inferior nasal concha bone nasal bone middle nasal concha vomer bone
Paranasal Sinuses frontal sinus ethmoid sinus maxilary sinus sphenoid sinus
coronal suture sagittal suture lambdoidal suture Cranium frontal bone parietal bon occipital bone
Ventral Skull palatine process palatine bone vomer bone temporal bone external occipital protuberance sphenoid bone styloid process mastoid proces occipital bone
carotid canal jugular foramen magnum Occipital bone occipital condyle
squamosal suture lacrimal bone temporal bone external acoustic meatus mandibular condyle In mandibular fossa Lateral Skull
zygomatic arc sphenoid bone sutural bone mastoid process styloid process Lateral Skull coronoi d process ramus angle body mandible
cribriborm plate crista galli lesser wing greater wing optic canal intenal acoustic meatus sella turcica ugular foramen jugular Internal Skull
Hyoid + external acoustic meatus Hyoid bone temmporal mandibular joint
________ Sagittal
Coronal Lambdoid Squamous
Overview of Skull Geography • Facial bones form the anterior aspect • The cranial bones enclose the brain
Vault • The cranial vault or calvaria forms the superior, lateral, and posterior aspects of skull • The cranial base forming the inferior aspect of skull
Cranial Base • Cranial base forms the skull’s inferior aspect • Three prominent ridges divide the base into fossae • The brain rests on these cranial fossae completely enclosed by the cranial vault • The brain occupies the cranial cavity
Cranium • The 8 cranial bones include; 2 parietal, 2 temporal frontal, occipital, sphenoid, ethmoid • Cranium is self- bracing allowing the bones to be thin, yet strong
Occipital bone • Forms most of the posterior wall and base of skull • Articulates with parietal & temporal • Joins w/ sphenoid in the cranial floor • Forms internal walls of posterior cranial fossa
Occipital bone - Int. landmarks • Hypoglossal canal, Posterior cranial fossa
Temporal Bone • Forms the inferolateral aspects of the skull • Parts of the cranial floor • Divided into four regions; squamous tympanic, mastoid, and petrous-(int)
Temporal Bone • The internal petrous region contributes to the cranial base • The petrous region and the sphenoid bone form the middle cranial fossa
Temporal Bone - landmarks • Zygomatic process – Meets the zygomatic bone – Forms the cheek • Mandibular fossa – Receives condyle of mandible
Temporal bones - landmarks • Stylomastoid foramen – exit for facial nerve • Carotid canal – entrance for the carotid artery which supplies blood to cerebral hemispheres
Sphenoid bone • Bone spanning the width of middle cranial fossa • Articulates as central wedge of all cranial bones • Consists of central body and three processes; greater and lesser wings and pterygoid process (pos. view)
Sphenoid - landmarks • • • Sella turcica (enclosure for pituitary gland) Optic foramina (passage of optic nerves) Superior orbital fissure (Nerves III, IV, V enter orbit) Foramen rotundum & ovale (Cranial Nerve V to face) Foramen spinosum (Middle meningeal artery)
Ethmoid bone • Forms most of the area between the nasal cavity & orbits of eyes • Lies between nasal bones & sphenoid • Complex shape gives rise to nasal septum, sinuses and cribiform plate
Ethmoid bone - landmarks • Cribiform plates – Forms roof of nasal cavity • Olfactory formina – Olfactory nerves enter brain • Crista galli – Attachment of the dura mater which secures brain in cavity
Facial bones • Consists of 14 bones w/ only mandible and vomer unpaired • Others include maxillae, lacrimals, nasals, zygomatics, inferior nasal conchae, and palatines (not pictured)
Mandible • Forms the lower jaw • Largest, strongest bone of the face • It has a body and two upwardly projecting sections called rami • Houses lower dentition
Mandible - landmarks • • Mandibular angle Mandibular notch Coronoid process Mandibular condyle Alveolar margin Mandible formina Mental formina Ramus of mandible
Maxillary bone • Forms upper jaw and central portion of facial skeleton • Fused medially • Articulates with all facial bones except mandible • Upper dentition • Forms 2/3 of hard palate of the mouth Zygomatic process Maxillary bone
Maxillary bones - landmarks • Alveolar margin – Upper dentition • Frontal process – Forms lateral aspects of nose • Zygomatic process – Articulates with zygomatic bone • Maxillary sinuses – (Fig. 7. 11)
Palatine bones • The horizontal plates forms the posterior portion of hard palate • Vertical plate forms part of the posterolateral wall of nasal cavity and a small portion of orbit
Palatine bones - landmarks • Horizontal plate – Posterior section of hard palate • Vertical plate – Part of the posteriolateral walls of nasal cavity • Orbital surface – Part of inferior medial aspect of orbit
Vomer • Forms part of the nasal septum • Discussed with the nasal cavity
Vomer - landmarks • Plow shape – Divides nasal septum into right and left parts
Inferior Nasal Conchae - Landmark • The Inferior nasal conchae is just one of three in the nasal cavity • Superior and middle concha are on the Ethmoid bone
The Orbits
Paranasal sinuses • Note positioning around nasal cavity
Paranasal sinuses • • Sphenoid sinus Frontal sinus Ethmoid sinus Maxillary sinuses
Hyoid bone • Body – Neck muscle attachment • Greater horn – Neck muscle attachment • Lesser horn
TMJ
TMJ Capsule
TMJ Capsule
TMJ Motions
TMJ Motions
The Skull: Fractures • Egg Shell Fracture of the Parietal bones. • Results from a fall or blunt force to the head
The Skull: Fractures • Another example of an egg shell fracture.
Knife in Skull Above Orbit AP Projection
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