GEN ANA PRELIM

• The mandible is united to the skull by mobile, synovial TMJs
• Connective tissue between bones

  Forms sutural ligaments
• Skull vault (calvarium)


  Upper part of the cranium forming the roof and side walls of the cranial cavity
• Bones of the vault

  Composed of external and internal tables of compact bone separated by a layer of spongy bone called the diploe
• Base of skull

  Lowest part of cranium forming the floor of the cranial cavity
• Cranial cavity


  Space containing the brain
• Nasal bones


  • Forms the bridge of the nose
  • Lower borders with the maxillae make the anterior nasal aperture
• Bones of the vault form

  Membranous ossification
• Maxillae

  • Form the upper jaw
  • Intermaxillary suture is at the midline where 2 maxillae meet
  • Infraorbital foramen perforates the maxilla below the orbit
  • Alveolar process projects downward
  • Alveolar arch carries upper teeth
  • Maxillary sinus is a large cavity lined with mucous membrane
• Nasal cavity

  • Divided into two by the bony nasal septum largely formed by the vomer and perpendicular plate of ethmoid
  • Superior and middle conchae project into the nasal cavity from the ethmoid on each side
  • Inferior conchae are separate bones
• Skull

  Composed of several separate bones united at immobile joints called sutures
• Frontal bone articulates with the parietal bone

  At the coronal suture
• Zygomatic bone

  • Forms the prominence of the cheek and part of the lateral wall and floor of the orbital cavity
  • Perforated by foramina for zygomaticofacial and zygomaticotemporal nerves
  • Medially articulates with maxilla
  • Laterally articulates with the zygomatic process of the temporal bone to form zygomatic arch
• Internal table of bones of the vault

  Thinner and more brittle
• Orbitomeatal plane (Frankfurt plane)


  Natural horizontal cranial plane
• Mandible


  • Consists of a horizontal body and two vertical rami
• Skeleton of the head and neck

  • Skull
  • Middle ear ossicles
  • Hyoid bone
  • Cervical vertebrae
• Bones in the head and neck


  • Zygomatic bones
  • Maxillae
  • Nasal bone
  • Lacrimal bone
  • Vomer
  • Palatine bone
  • Inferior conchae
  • Mandible
• Frontal bone

  • Curves downward to make the upper margins of the orbits
  • Medially articulates with the frontal process of the maxillae and nasal bones
  • Laterally articulates with zygomatic bone
  • Contains frontal air sinuses and superciliary arches
  • Has a supraorbital notch near the orbital rim
• Parietal bones articulate with each other in the midline

  • At the sagittal suture
  • With the occipital bone at the lamboid suture
• Bones of the cranial base and facial skeleton form

  Endochondral ossification
• Bones of the skull

  • Cranial skeleton
  • Facial skeleton
• Orbital margins

  • Superior- frontal bone
  • Lateral- zygomatic bone
  • Inferior- maxilla
  • Medial- process of the maxilla and frontal bone
• Parietal bones articulate with the occipital bone behind

  At the LAMBOID SUTURE
• Ramus and body of the mandible

  Lie inferiorly
• Pterygoid hamulus is a curved spike bone at the inferior end of the medial pterygoid plate
• The thinnest part of the lateral wall of the skull is where the anteroinferior corner of the parietal bone articulates with the greater wing of the sphenoid
• Pterygopalatine fossa communicates medially with the nasal cavity through SPHENOPALATINE FORAMEN
• Pterygopalatine fossa communicates anteriorly with the orbit through INFERIOR ORBITAL FISSURE
• Pterygopalatine fossa communicates superiorly with the cranial cavity through FORAMEN ROTUNDUM
• Superior and Inferior Temporal Lines

  • A single line from the posterior margin of the zygomatic process of the frontal bone and diverge as they arch backward
• Incisive foramen is in the anterior midline
• Bones that complete the skull at the side

  • Squamous part of the occipital bone
  • Temporal bone: Squamous, Tympanic, Mastoid process, Styloid process, Zygomatic process
  • Greater wing of sphenoid
• External occipital protuberance


  Roughened elevation in the midline of the occipital bone, gives attachment to muscles and ligamentum nuchae
• Foramina


  • Greater and lesser palatine foramina posterolaterally
  • Chonae (posterior nasal apertures) above the posterior edge of the hard palate
• The posterior parts of the two parietal bones articulate with each other

  With the intervening SAGITTAL SUTURE superiorly
• A groove for the cartilaginous part of the auditory tube lies behind the spine of the sphenoid, between the greater wing of the sphenoid and the petrous part of the temporal bone
• Mandible


  • Consists of a horizontal body and two vertical rami
• Parietal bones articulate with the squamous part of the occipital bone


  At the LAMBDOID SUTURE inferiorly
• Large foramen ovale and small foramen spinosum pierce the greater wing of the sphenoid posteroIaterally to the lateral pterygoid plate