Major Bones of the Cranium

skull

cranium and mandible

mandible

lower jaw

cranium

skull without mandible

how many bones are in the skull?

29

‘auditory ossicles’ refers to what body part?

ear

hyoid refers to what body part?

the throat

braincase refers to?

Frontal, occipital, parietals, sphenoid, temporals, ethmoid

face refers to which bones?

Inferior nasal conchae; lacrimals; mandible, maxillae, nasals, palatines, vomer, zygomatic

endocranial

inside the cranium

ectocranial

outside the cranium

The Frankfurt Plane

In the anatomical position, the skull is oriented so that the inferior margins of the orbits and the superior margin of the external acoustic meatus are horizontal, this is called the Frankfurt plane.

frontal bone, where and how many?

1

parietal bones, where and how many?

2

sphenoid bone, where and how many?

1

temporals, where and how many?

2

occipital, where and how many?

1

maxilla, where and how many?

1 - upper jaw

mandible, how many and where?

2 (but they’re fused) - lower jaw

Features

• describe unique anatomical structures

• unique identifiers for each element like a birthmark or tattoo

process

a bony prominence (a bit that sticks out)

eminence

a bony projection (usually not as prominent as a process)

fossa

a depressed area, usually broad and shallow (French fosse = grave)

foramen

an opening throuh a bone, usually a passage for blood vessels and nerves. |(typically, a small, smooth-walled hole)

sinus

a cavity within a cranial bone (e.g. frontal sinuus; maxillary sinus)

sulcus

a long, wide groove

† means what?

endocranial view

Frontal bone (braincase), fill in the blanks.

an ectocranial view anterior

*also called supercillary ridge

squama refers to what?

scale, like fish-scale

frontal bone (braincase), fill in the blanks

an endocranial view (posterior)

name these features of the right partietal?

endocranial view (medial)

temporal bones key features

• Squama

• Zygomatic process

• Mandibular or glenoid fossa

• External Auditory Meatus (EAM)

• Mastoid process

• †Petrous pyramid

occipital bone - fill in the blanks

ectocranial, pposterior view

occipital bone, name the missing features

occipital bone, endocranial anterior view

†cruciform eminence

name the bone highlighted in pink

sphenoid bone (looks like a butterfly)

name the 4 key features of the maxilla/maxillae (technically 2 bones that ossify from seperate centres but typically fuse during utero)

• Piriform aperture

• Frontal process

• Zygomatic process

• Alveolar process

labell 3 key features of the maxilla

• Alveoli

• Infraorbital foramen

• Anterior nasal spine

name the missing feature of the maxilla

the †Maxillary sinus