Anatomy of the Skull

Overview

• The human skull consists of 22 bones
  • 8 Cranial Bones: Enclose the brain in the neurocranium
  • 14 Facial Bones: Form the facial skeleton
  • 6 Ear Bones: Known as ossicles

Cranial Bones

• Occipital Bone: Located at the back of the skull
• Sphenoid Bone:
  • Located in the middle, inferior part of the neurocranium
  • Resembles a butterfly
  • Articulates to form the orbit
• Ethmoid Bone:
  • Located between the eyes
  • Separates the nasal cavity from the brain
• Frontal Bone:
  • Forms the forehead
  • Has vertical and horizontal sections
• Parietal Bones (Pair):
  • Form the top and sides of the neurocranium
  • Quadrilateral in shape
• Temporal Bones (Pair):
  • Located at the sides and base of the skull
  • Overlaid by the temples
  • Contain the ossicles (middle ear bones)

Middle Ear Bones (Ossicles)

• 3 Ossicles per side: Malleus (Hammer), Incus (Anvil), Stapes (Stirrup)
• External Acoustic Meatus: The ear canal connecting outer and middle ear
• Internal Acoustic Meatus: Connects inner ear to the posterior cranial fossa

Facial Bones

• Mandible:
  • Jawbone, largest facial bone
  • Only movable skull bone
• Vomer:
  • Forms part of the nasal septum
  • Articulates with sphenoid, ethmoid, palatine, and maxillary bones
• Maxillae (Pair):
  • Form upper jaw and hard palate
  • Fused at intermaxillary suture
• Palatine Bones (Pair):
  • Form part of the hard palate
  • Located at the back of the nasal cavity
• Nasal Bones (Pair):
  • Form the bridge of the nose
  • Joined at internal suture
• Nasal Concha:
  • Thin bony elements in nasal cavities
  • Include inferior, middle, and superior concha
• Zygomatic Bones (Pair):
  • Known as cheekbones
  • Articulate with maxilla, temporal, sphenoid, and frontal bones
• Lacrimal Bones (Pair):
  • Small bones in the orbit's medial wall

Conclusion

• Review of cranial and facial bones
• Additional topics to be covered in future discussions